Wetlands of the Northeast: Results of the National Wetlands Inventory

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Wetlands of the Northeast:
Results of the National Wetlands Inventory
April 2010
U.S. Fish & Wildlife ServiceWetlands of the Northeast:
Results of the National Wetlands Inventory
April 2010
U.S. Fish & Wildlife Service
Ralph W. Tiner
Regional Wetland Coordinator
Northeast Region
U.S. Fish and Wildlife Service
300 Westgate Center Drive
Hadley, Massachusetts 01035ii
This document should be cited as: Tiner, Ralph W. 2010. Wetlands of the Northeast: Results of the National Wetlands Inventory. U.S. Fish and Wildlife Service, Northeast Region, Hadley, MA. 71 pp.iii
TABLE OF CONTENTS
Wetlands of the Northeast: Results of the National Wetlands Inventory
Executive Summary……………………………………………………………………………………………… v
Acknowledgments……………………………………………………………………………………………… vi
Introduction ……………………………………………………………………………………………………… 1
Study Area …………………………………………………………………………………………………………1
Overview of the Region’s NWI Program …………………���…………………………………………………… 3
Wetlands Inventory ……………………………………………………………………………………………………3
Special Projects ……………………………………………………………………………………………………… 7
Assessing Wetland Changes in the Region ……………………………………………………………………… 7
Expanding NWI Data for Landscape-level Functional Assessment: NWIPlus ……………………………… 7
Potential Wetland Restoration Site Mapping …………………………………………………………………… 9
Assessing Natural Habitat Integrity for Watersheds ………………………………………………………… 9
NWI Mapping for the Northeast ………………………………………………………………………………… 11
Current Status of Mapping ………���…………………………���………………………………………………… 12
Mapping Limitations ………………………………………………………………………………………………… 13
The National Wetlands Database …………………………………………………………………………………… 15
Aggregating Wetland Types for this Report ……………………………………………………………………… 15
Interpretation of Results …………………………………………………………………………………………… 15
Extent of Wetlands and Deepwater Habitats in the Northeast ……………………………………………………17
Summary ………………………………………………………………………………………………………… 22
References ……………………………………………………………………………………………………… 23
Appendix A. List of Contributors to the NWI …………………………………………………………………… 25
Appendix B. Overview of the Service’s Wetland Classification System ………………………………………… 26
Appendix C. List of Regional NWI Publications ………………………………………………………………… 31
Appendix D. Tabular Summaries of NWI Findings for Each State and the District of Columbia ………………… 39
List of Tables
Table 1. Geographic areas where NWIPlus data have been created or are planned for 2010-11 ……………… 8Table 2. Some limitations of NWI data ………………………………………………………………………………14Table 3. Type and coverage of NWI data for each Northeast state and the District of Columbia ………………16Table 4. Wetland acreage for northeastern states and the District of Columbia …………………………………18Table 5. Deepwater habitat acreage for northeastern states and the District of Columbia …………………… 19Table 6. Percent of land area mapped as wetland by the NWI …………………………………………………… 19Table 7. Acreage of major tidal wetland types across the region ………………………………………………… 20Table 8. Acreage of major palustrine wetland types across the region ……………………………………………21
(Note: See Appendix D for acreage summary tables for each state and the District of Columbia)
List of Figures
Figure 1. Ecoregions of the northeastern United States according to Bailey (1994). ……………………………2Figure 2. Example of NWI map produced for Milton, Delaware. …………………………………………………4Figure 3. Custom NWI map for the Milton, Delaware area printed from the “Wetlands Mapper” showing a portion of the area covered in the previous figure. ………………………………………………………………… 5
Figure 4. NWI data for the Milton, Delaware area printed on a topographic base from the U.S. Geological Survey’s National Map. ……………………………………………………………………………………………… 6
Figure 5. Application of natural habitat integrity indices to Midwest states. …………………………………… 10Figure 6. Status of the NWI in the Northeast Region as of September 2009. ……………………………………12Figure 7. Era of imagery for NWI mapping in the Northeast Region as of September 2009. ………………… 12iv
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Executive Summary
Wetlands of the Northeast: Results of the National Wetlands Inventory
The U.S. Fish and Wildlife Service established the National Wetlands Inventory (NWI) in the mid-1970s to map the nation’s wetlands and deepwater habitats. Since then, the NWI has completed at least one phase of mapping for all northeastern states, except New York where roughly three-quarters of the state has been inventoried. For most areas, NWI maps have been converted to digital geospatial data which facilitates generation of acreage summaries of the NWI findings. State reports have been published for several states (Rhode Island, Connecticut, New Jersey, Delaware, and Maryland) and acreage summaries published for most other northeastern states. Since these reports were published, NWI data have been updated for many areas. This report summarizes current NWI data (as of September 2090) for each state from Maine through Virginia and the District of Columbia.
To date, nearly 9 million acres of wetlands have been inventoried by the NWI and are included in its national digital database. Three states had more than one million acres of wetlands: Maine (2.175M acres), New York (1.573M acres with only 74% of the state completed in digital format), and Virginia (1.471M acres). Wetland density (wetland acres/unit area) was highest in states dominated by the coastal plain - Delaware had the highest density of wetland with 21 percent of the state covered by wetland, followed closely by New Jersey with 20 percent. The presence of Chesapeake Bay and its tidal wetlands led to Virginia and Maryland being top-ranked in the acreage of tidal wetlands: Virginia with over 444,000 acres and Maryland with nearly 295,000 acres. New Jersey was the only other state with more than 250,000 acres of tidal wetlands. Estuarine emergent wetlands (salt and brackish marshes) were the predominant tidal wetland type in all coastal states except Maine where estuarine unconsolidated shores (tidal flats) were most common. Maine possessed the most palustrine wetland acreage with about 2 million acres mapped, whereas New York (based on digital wetland data for only 74% of the state) and Virginia both had over one million acres. Other states with more than 400,000 acres of these wetlands were New Jersey, Massachusetts, Maryland, and Pennsylvania. Forested wetlands were the dominant palustrine wetland type in all states, except in West Virginia where unconsolidated bottoms (ponds) were the most common type. Maine had the most acreage of forested and scrub-shrub wetlands mapped with over one million acres and nearly 550,000 acres, respectively.
In addition to creating NWI maps and geospatial data, the Region’s NWI Program has produced a variety of other products including multi-state wetland trends reports, local inventory of wetland change reports, watershed-based wetland characterizations and preliminary functional assessments, and inventories of potential wetland restoration sites. These products plus the digital geospatial data and accompanying status reports have greatly increased our knowledge of the extent, distribution, and diversity of wetlands, their status and trends, wetland functions, and opportunities for their restoration. As such, the NWI has provided vital information to various Service programs, other federal agencies, state agencies, and others that has been used to help protect, conserve, and restore our nation’s wetlands.vi
Wetlands of the Northeast: Results of the National Wetlands Inventory
Acknowledgments
The National Wetlands Inventory (NWI) Program has been actively mapping the nation’s wetlands since the mid-1970s and many people have contributed to the program’s success. For the Northeast Region the actual mapping work was done mostly by a large cadre of photointerpreters and image analysts at the University of Massachusetts (Amherst, MA), the Conservation Management Institute of Virginia Tech University (Blacksburg, VA) and Regional NWI staff with hardcopy maps produced by the NWI Center at St. Petersburg, Florida. Key personnel that should be recognized for the interpretation work - the foundation for the NWI -include former Regional NWI staff - John Anderson, Herbert Bergquist, Anthony Davis, Gabriel DeAlessio, Kelly Drake, David Foulis, Joanne Gookin, Irene Huber, Todd Nuerminger, Sue Schaller, Matt Starr, and William Zinni, former UMass interpreters - chiefly Judy Harding, John LeBlanc, Meredith Borenstein, Kim Santos, Frank Shumway, Jennifer Silva, George Springston, and Janice Stone, and Virginia Tech staff - mainly Matt Fields, Nicole Furman, Kevin McGuckin, and Pamela Swint. Laura Roghair (Virginia Tech) provided analysis of the NWI database that was used to prepare the acreage summaries for this report. The NWI work over the past 35 years was done under the direction of Regional Wetland Coordinator Ralph Tiner with quality control support provided mainly by Assistant Coordinators John Organ, Glenn Smith, and John Swords. Peer review of this report was done by William Kirchner, Jo Ann Mills, John Swords, and Bill Wilen. Gina Jones prepared the report for final publication. Special thanks go to all these individuals plus the agencies and organizations that have contributed in various ways to the success of the NWI Program (Appendix A). 1
Wetlands of the Northeast: Results of the National Wetlands Inventory
Introduction
The Northeast Region of the U.S. Fish and Wildlife Service has been actively mapping wetlands in thirteen states
since the mid-1970s when the National Wetlands Inventory (NWI) Program was established. The NWI Program
was created in 1974 to map the country’s wetlands and provide the Service’s biologists and others with information
on the distribution and diversity of wetlands to aid in wetland conservation efforts. This was the first time that the
federal government produced detailed maps showing the location of the diversity of wetlands that occur across the
nation. The maps serve as invaluable aids for local planning and natural resource conservation.
The purpose of this report is three-fold to: (1) briefly describe the variety of activities performed by the Region’s
NWI Program, (2) increase awareness of the availability of regional NWI reports, and (3) present the findings of the
NWI’s 35 years worth of effort mapping wetlands in the Northeast.
Study Area
The Northeast Region encompasses thirteen states from Maine through Virginia including West Virginia. Major
watersheds in the Region include the drainage basins of the Penobscot, Merrimack, Connecticut, Hudson, Delaware,
Susquehanna, and Potomac Rivers. The Region also contains large coastal embayments including Chesapeake Bay
(the largest estuary in the United States), Delaware Bay, and Long Island Sound plus the Gulf of Maine with its
irregular rocky shoreline and marine-dominated ecosystems. From a physiographic perspective, the region ranges
from the New England-Adirondack Highlands in the north to the Atlantic Coastal Plain, Piedmont, and Appalachian
Highlands in the south, with the major ecosystems varying from boreal forests to broadleaf forests and pine or
mixed pine/hardwood flatwoods (Figure 1). The Region contains a wealth of wetlands including boreal forested
wetlands, bogs, fens, marshes, wet meadows, floodplain wetlands, coastal plain flatwoods, and tidal marshes (see
Tiner 2005 for general descriptions of these types).
2
Wetlands of the Northeast: Results of the National Wetlands Inventory
Figure 1. Ecoregions of the northeastern United States according to Bailey (1994).
212 – Laurentian Mixed Forest Province, M212 – Adirondack-New England Mixed Forest-Coniferous Forest-Alpine
Meadow Province, 221 – Eastern Broadleaf Forest (Oceanic) Province, M221 – Central Appalachian Broadleaf Forest-
Coniferous Forest-Meadow Province,
222 – Eastern Broadleaf Forest (Continental) Province, 231 – Southeastern Mixed Forest Province, and 232 – Outer
Coastal Plain Mixed Forest Province.
3
Wetlands of the Northeast: Results of the National Wetlands Inventory
The Region’s NWI Program is responsible for
conducting the wetland inventory in thirteen
northeastern states from Maine through Virginia. The
main focus of this effort is to produce wetland maps (now
geospatial data) following national standards established
by the Program. Those standards have been recently
adopted as the federal wetland mapping standard by
the Federal Geographic Data Committee (FGDC 2009)
for all federally-funded wetland mapping projects.1
Besides the mapping, the Region’s NWI Program
performs studies to provide the Service and others with
vital information to assist wetland conservation efforts.
This work includes regional and local wetland change
studies, watershed-based wetland characterizations, and
landscape-level assessments of wetland functions.
Wetlands Inventory
The NWI employs conventional photointerpretation
techniques upgraded to utilize modern-day computer
technology to identify, classify, and delineate wetlands
and deepwater habitats. This work is done by image
analysts who interpret spectral signatures from aerial
photographs or digital imagery, separate wetlands from
deepwater habitats from uplands (dryland), delineate
boundaries, and classify wetlands and deepwater
habitats according to the federal government’s official
wetland classification system (Cowardin et al. 1979;
an overview of this system is provided in Appendix
B). Prior to the computer age and desktop mapping,
the interpretations were recorded by pen and ink on
an acetate overlay attached to an aerial photograph.
The annotations were then compiled into map form by
cartographers using zoom transfer scopes at the NWI
Center in St. Petersburg, Florida. Maps were then
digitized manually for computer applications. Today,
the entire operation is done by image analysts on the
computer using geographic information system (GIS)
technology.
At the Program’s inception, the NWI produced maps
at a scale of 1:250,000 map (covering approximately
7,400 square miles). Service field personnel were not
satisfied with this product so eventually large-scale
(1:24,000) maps became the standard product (Figure
2). As computer mapping technology evolved, the
NWI maps were digitized for GIS applications. In the
mid-1990s, the NWI discontinued production of paper
maps in favor of distributing NWI data via online
“mapping tools” where people could make custom
maps for their area of interest. Today, the NWI serves
its data through a tool called the “Wetlands Mapper”
which generates a planimeter map (Figure 3). NWI
data can also be displayed on a topographic map via
the U.S. Geological Survey’s National Map (Figure 4)
or on a current aerial image via a link to Google Earth.
The general public can access and display NWI data
using these tools. More sophisticated GIS users can
connect their applications to real-time data directly
through an online wetland mapping service or download
NWI data for their own applications. Data can be
downloaded by quad or by state. For an overview of the
varied uses of NWI data, see “Status Report for the
National Wetlands Inventory Program: 2009” (Tiner
2009: http://www.fws.gov/wetlands/_documents/gOther/
StatusReportNWIProgram2009.pdf).
Overview of the Region’s NWI Program
1 This standard should be applied to all federal grants involving wetland mapping to insure that such mapping can be added to the NWI’s wetlands
master geospatial database.
4
Wetlands of the Northeast: Results of the National Wetlands Inventory
Figure 2. Example of NWI map produced for Milton, Delaware.
5
Wetlands of the Northeast: Results of the National Wetlands Inventory
Figure 3. Custom NWI map for the Milton, Delaware area printed from the “Wetlands Mapper” showing a portion of the
area covered in the previous figure.
6
Wetlands of the Northeast: Results of the National Wetlands Inventory
Figure 4. NWI data for the Milton, Delaware area printed on a topographic base from the U.S. Geological Survey’s
National Map.
7
Wetlands of the Northeast: Results of the National Wetlands Inventory
Special Projects
While wetland mapping remains the foundation of
the NWI, the Region’s NWI Program has produced
a variety of ancillary products to expand the level of
information provided by the program. These special
projects have substantially added to our knowledge of
Northeast wetlands.
Assessing Wetland Changes in the Region
Knowing how and why wetlands are changing is
vital information for resource managers. The NWI
employs two basic approaches for evaluating wetland
changes: 1) statistically based probabilistic sampling
and 2) inventory of change.2 The former approach
was developed for estimating status and trends of the
nation’s wetlands and involves analyzing changes in
four-square mile plots (Frayer et al. 1983). The NWI
has produced national reports on wetland status and
trends using this approach since the 1980s (e.g., Tiner
1984 and Dahl 2006). This approach provides useful
information for federal agency policy analysts but given
its national focus is not as useful for guiding wetland
conservation efforts at state and local levels. The
Region used this approach for estimating trends in
the five-state Mid-Atlantic region and the Chesapeake
Bay watershed (e.g., Finn and Tiner 1986). The second
approach – inventory of change – was developed by the
Region’s NWI Program for obtaining more detailed
and area-specific information on the nature of local
changes and the underlying causes than generated by
the Service’s national status and trends study. This
approach does not produce estimates of changes, but
instead is an inventory of wetland changes produced
by comparing aerial imagery for the entire geographic
area. Inventories of change have been performed for
certain counties and smaller areas representing just a
couple of 1:24K maps (see Appendix C for a list of these
publications). This type of information is most useful
for analyzing the effectiveness of government efforts
to conserve and protect wetlands in specific geographic
areas. As NWI data are updated in the Northeast,
the Region’s NWI Program plans to produce these
inventories of change, as funding permits, to report on
wetland changes for specific geographic areas as large as
individual states.
Expanding NWI Data for Landscape-level Functional
Assessment: NWIPlus
NWIPlus is an expanded database where other
descriptors are added to the standard NWI database
to improve its utility for preparing more detailed
characterizations of wetland resources and for
predicting wetland functions at the landscape level. In
the 1970s and 1980s, the basic need for wetland data
was inventory-based, that is, knowing where wetlands
were on the landscape and how they differed in terms
of vegetation type and hydrology. With strengthened
wetland regulations since the late 1980s and early 1990s,
another need surfaced - wetland functional assessment.
As techniques were being developed for on-the-ground
assessment of wetland functions, the Region’s NWI
Program sought ways to enhance its inventory so
that landscape-level assessments of wetland functions
could be derived from its database. To accomplish
this, hydrogeomorphic-type descriptors were created
to describe landscape position (i.e., the relationship
between a wetland and a watercourse or waterbody
if present), landform (the shape or physical form of a
wetland), and water flow path (the directional flow of
water). In addition, other descriptors were formulated
to better address the diversity of waterbodies, especially
for ponds, since every wetland trend study has shown
an increase in pond acreage while vegetated wetlands
declined. The type of pond and its landscape context
provide important information for assessing pond
functions. Collectively these descriptors are referred
to as LLWW descriptors (landscape position, landform,
water flow path, and waterbody type; Tiner 2003a).
The NWI has worked with wetland specialists in the
Northeast to develop correlations between wetland
functions and the wetland characteristics recorded
in the NWIPlus database (Tiner 2003b). These
techniques have been used to produce watershed-based
wetland characterizations and preliminary functional
assessments for a number of watersheds in the
Northeast (Table 1).3 A list of available reports is given
in Appendix C.
2 Wetland change analysis is not done by comparing maps since maps produced during different stages of the inventory may not be comparable in
quality. Image-to-image analysis produces a highly accurate and reliable assessment of wetland gains, losses, and changes in type for study areas.
The NWI performs image-to-image analysis for identifying these changes.
3 These techniques have been adopted by several states across the country for their wetland inventories and for utilizing existing wetland data to
predict wetland functions (see article in forthcoming May-June 2010 issue of the National Wetlands Newsletter).
8
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table 1. Geographic areas where NWIPlus data have been created or are planned for 2010-11. A report characterizing
wetlands and their functions was produced or is planned for most areas.
State Geographic Area
Maine Casco Bay watershed
Massachusetts Boston Harbor area, Cape Cod, Nantucket, and Martha’s Vineyard
Rhode Island Entire state
Connecticut Entire state (in progress)
New York Long Island (in progress); New York City water supply watersheds; eleven small
watersheds across the state: Catherine Creek, Cumberland Bay, Hudson River-Snook Kill,
Peconic River, Post Creek to Sing Sing Creek, Salmon River to South Sandy Creek, Sodus
Bay to Wolcott Creek, Sodus Creek, Sucker Brook to Grass River, Upper Tioughnioga
River, and Upper Wappinger Creek
New Jersey Entire state (in progress)
Delaware Nanticoke watershed, entire state (in progress)
Maryland Nanticoke watershed, Coastal Bays watershed
9
Wetlands of the Northeast: Results of the National Wetlands Inventory
Potential Wetland Restoration Site Mapping
Another area of growing interest in wetland
conservation is wetland restoration. In the early
1990s, the Region’s NWI Program worked with the
Massachusetts Executive Office of Environmental
Affair’s Wetlands Restoration and Banking Program
and the University of Massachusetts on special projects
designed to identify potential wetland restoration sites
for some of the state’s watersheds. At that time, the
Massachusetts Wetlands Restoration and Banking
Program applied a watershed-based wetland restoration
approach aimed at targeting wetland restoration in
strategic locations that could help alleviate watershed
problems (e.g., flood damages, degraded water quality,
and fragmented wildlife habitat). The NWI assisted
in developing this approach which ultimately gave the
NWI Program the vision and capability for producing
potential wetland restoration site inventories. Potential
wetland restoration sites include former wetlands that
have been drained or filled but are still in a condition
where restoration is possible (Type 1 restoration sites)
and existing wetlands that have functions impaired by
ditching, excavation, impoundment, or cultivation (Type
2 restoration sites). The former sites are identified
using soil maps and locating hydric soil areas that are
not mapped as NWI wetlands and do not have any
buildings or other structures built upon them. These
restoration site inventories are now often part of
watershed-based wetland inventories and functional
assessments as the data used in these investigations
make it easy to document potential restoration sites.
Through the watershed assessments, it is also possible
to identify sites for possible restoration of streamside
(riparian) vegetation. Depending on project funding and
objectives, the Region’s NWI Program is attempting to
include wetland restoration site inventories as part of its
standard NWI updating procedures.
Assessing Natural Habitat Integrity for Watersheds
Looking beyond wetlands to the entire watershed
is important to assess the “health” of wetlands and
waters since activities in the surrounding landscape
significantly affect water quality and habitat quality of
wetlands. The condition of wetland and stream buffers
is particularly important for wetland and aquatic
wildlife. The widespread availability of land use/cover
geospatial data made it possible to integrate NWI data
with these data to evaluate and report on the condition of
natural habitat surrounding wetlands and waterbodies
and for watersheds as a whole. To accomplish this, the
Region’s NWI Program developed a set of “natural
habitat integrity indices” that can be used for reporting
on the condition of natural habitats for large geographic
areas – a suite of useful metrics for an environmental
report card (Tiner 2004). Thirteen indices were created:
seven addressing habitat extent (i.e., the amount of
natural habitat occurring in the watershed and along
wetlands and waterbodies), four dealing with habitat
disturbances (emphasizing human-induced alterations
to streams, wetlands, and terrestrial habitats), and one
composite index. The eight “natural habitat extent
indices” are natural cover, river corridor integrity,
stream corridor integrity, vegetated wetland buffer
integrity, pond buffer integrity, lake buffer integrity,
wetland extent, and standing waterbody extent. The
four “habitat disturbance indices@ involve dammed
stream flowage, channelized stream flowage, wetland
disturbance, and habitat fragmentation by roads. The
last index - “composite natural habitat integrity index”
– may be calculated in two ways: one is comprised of
the weighted sum of the habitat extent indices minus
the sum of the disturbance indices (weighted composite
natural habitat integrity index), while the alternative is
a simple sum of the extent indices minus the sum of the
disturbance indices (simple summed composite natural
habitat integrity index). These indices were intended to
augment, not supplant, other more rigorous, fine-filter
approaches for describing the ecological condition of
watersheds and for examining relationships between
human impacts and natural resources. The indices can
be used as one metric for an environmental report card
that addresses the changing quality of lands and waters
in specific geographic regions. NWI has applied the
indices to special projects funded by the Service or state
agencies interested in assessing the overall condition
of natural habitat for individual watersheds (e.g., Tiner
and Bergquist 2007). An adjacent Service region (Great
Lakes Region, Region 3) has also applied these indices to
their entire region to produce a map of watershed health
(Figure 5), while the states of Montana and Virginia have
adapted these indices for assessing their watersheds
(e.g., Vance et al. 2009, Ciminelli and Scrivani 2007).
10
Wetlands of the Northeast: Results of the National Wetlands Inventory
Figure 5. Application of natural habitat integrity indices to Midwest states by U.S. Fish and Wildlife Service, Region 3,
Division of Conservation Planning. (Note: This is an early version of the application, contact the Region for the latest
edition.)
11
Wetlands of the Northeast: Results of the National Wetlands Inventory
NWI Mapping for the Northeast
The NWI has complete coverage of wetland data for
all Northeast states except New York. Some areas
have been updated once or twice since the NWI was
initiated in the mid-1970s and state reports have been
published in one form or another for all states except
Massachusetts, Vermont, New York, and Virginia,
although preliminary statistics based on the original
mapping were published for the former two states (see
publications list, Appendix C). Readers should recognize
that an inventory is not a one-time mapping effort,
but instead it is an ongoing process because wetlands
are changing due to both natural forces and human
activities. Also advances in mapping technology make
it possible to improve the accuracy and completeness of
the inventory. New data have been added to the database
for many states, making the previous acreage summaries
reported by NWI obsolete. The most recent findings are
reported in the last major section of this report “Extent
of Wetlands and Deepwater Habitats in the Northeast.”
12
Wetlands of the Northeast: Results of the National Wetlands Inventory
Current Status of Mapping
The status of NWI mapping for the Region as of September 2009 is shown in Figure 6. This report summarizes NWI
acreage data where digital data are available (green areas) as data for other areas are either not available (pink) or
only available in hardcopy maps (tan areas).
The effective date of the NWI across the Region is shown in Figure 7. NWI data are derived not from a single time
period as funding and imagery constraints make this impossible. While most of the data are from the mid-1980s
(green areas), some of the data are from the 1970s (purple areas) and many areas have been recently updated (blue
and red areas). In some areas of the region, development is not occurring at a rapid pace and therefore the mid-
1980s data may still reflect current conditions. The program continues to work in priority areas.
Figure 6. Status of the NWI in the Northeast Region as of
September 2009. Non-digital means only hardcopy maps
are available. The data summaries presented in this
report were derived from the areas shown in green on this
map.
Figure 7. Era of imagery for NWI mapping for the
Northeast Region as of September 2009.
13
Wetlands of the Northeast: Results of the National Wetlands Inventory
Mapping Limitations
The mapping techniques of the NWI have evolved over
time. NWI mapping has improved for a number of
reasons including the availability of higher resolution
imagery, advances in GIS technology, the ability to
integrate NWI data with other geospatial data sources,
and standardized techniques for wetland identification
and delineation. With any mapping effort, there are
limitations due to scale, image quality, and other factors.
Given these considerations, it is impossible to map
every wetland and NWI data are no exception. Some
limitations of NWI mapping are identified in Table 2.
The data presented in this report were derived from
mapping performed using a variety of imagery sources
and during times where our knowledge of wetlands grew
exponentially.
The source imagery affects a number of factors in
wetland mapping: scale (related to smallest wetland
that can be mapped), the emulsion (ability to detect
wetlands), the timing (seasonality affects ability to
detect and classify wetlands), and the date (relates to
the currentness of the inventory, especially in rapidly
developing areas). Since the NWI utilized different
imagery during the course of the inventory, the date
of the imagery used in preparing the NWI can be used
to interpret the mapping detail as follows (Figure 7).
The 1970s imagery (1:80,000 black and white aerial
photography) generally yields a target mapping unit
(tmu) of 3-5 acres. This means that most wetlands
larger than this size range should be mapped, while
smaller wetlands are not consistently shown due to scale
issues. The black and white film also is not as useful for
detecting wetlands as color infrared film, so wetland
mapping is more conservative. The 1980s imagery
(typically 1:58,000 color infrared photography) allows for
a tmu of 1-3 acres in size, whereas the tmu for the 1990s
imagery (1:40,000 color infrared photography) is about 1
acre. The 2000-era imagery is digital imagery of varying
levels of resolution, but is equivalent or better than the
1:40K photography. The tmu for this imagery is ½ acre.
A drawback for some of the 2000-era imagery is that it
is sometimes true color rather than color infrared. True
color imagery is not as reliable for detecting wetlands as
color infrared. However, when interpreting the 2000-era
imagery, existing NWI data are usually being updated,
so the original data derived from color infrared aerial
photography plus the on-screen mapping process allow
the analyst to simultaneously view USDA soil mapping
with the net outcome being an improved wetland map.
While Figure 7 shows the general timeframe of the
imagery, it does not indicate the season in which the
imagery was acquired. Leaf-off imagery is best for
wetland detection. In some areas, such imagery was not
available for the NWI, so leaf-on imagery was used (e.g.,
central and western Pennsylvania). For these areas,
NWI produced a rather conservative inventory as many
forested wetlands were not detectable. When using
NWI data posted online on the Wetlands Mapper (http://
www.fws.gov/wetlands/Data/Mapper.html), readers
should read the accompanying metadata (click on
“Wetland Project Area Metadata”) to learn the specific
date of the imagery used. If summer imagery was the
primary source, the NWI data will be quite conservative.
In any event, when using NWI to determine whether
or not wetland is present on a given parcel of land,
individuals are encouraged to also consult the U.S.
Department of Agriculture’s web soil survey for the
presence of “hydric soils” (http://websoilsurvey.nrcs.
usda.gov/app/HomePage.htm).
14
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table 2. Some limitations of NWI data. (Adapted from Tiner 1999)
1. Target mapping unit (tmu). A tmu is an estimate of the minimum-sized wetland that the NWI is attempting to map and is
largely dependent on photo/image scale. Conspicuous wetlands smaller than the tmu (especially ponds) are often included in the
inventory.
2. Aquatic bed mapping. Since spring (leaf-off) imagery was typically used by the NWI, aquatic beds were not visible since
plants are just beginning to grow at this time and plant parts are well beneath the water’s surface. When observed in the field,
boundaries of these beds were approximated, but typically aquatic beds were included within the waterbody classification –
usually the unconsolidated bottom class.
3. Excessive flooding on imagery. In some cases, extreme high water conditions obscured the life form of the vegetation. While
in many cases, vegetation could be observed underwater, determining whether it was herbaceous or low-growing shrubs was
difficult. Consequently, some shrub wetlands may have been classified as emergent wetlands and vice versa.
4. Use of leaf-on imagery. In central and western Pennsylvania, leaf-on imagery was the only imagery available for the NWI and
resulted in a conservative wetlands inventory as many forested wetlands could not be detected on this imagery. For the rest of
the region, leaf-off imagery was typically available.
5. Temporarily flooded and seasonally saturated forested wetlands. These wetlands occur on higher portions of floodplains or on
nearly level broad plains such as the coastal plain (New Jersey south) or glaciolactustrine plain (e.g., western New York – former
shoreline of Great Lakes). They are among the more difficult wetlands to interpret especially when dominated by evergreen
species. USDA soil survey data have been used to help interpret these areas. NWI data collected prior to 1989 may not show
many of these areas. Availability of digital soils data since then has facilitated identification of these areas based on the presence
of hydric soils.
6. Estuarine wetlands, freshwater tidal wetlands, and tidal waters. Delineation of the break between estuarine and riverine tidal
systems and the oligohaline (slightly brackish) segment of estuaries were based on a combination of limited field observations,
image interpretation, and published reports. The boundaries should be considered approximate. Some tidal swamps may
be classified as nontidal forested wetlands where the upper limit of tidal influence was not mapped to its maximum upstream
penetration.
7. Tidal flats. Since the photos were not synchronized to capture low tide conditions, all tidal flats were not visible on the imagery
used. The boundaries of tidal flats were approximated from coastal and geodetic survey maps and topopgraphic maps when
necessary. Recognize that some of these features, especially sand flats, are dynamic and current locations and boundaries may be
different than those depicted on the maps or in the digital database, especially after major storm events (e.g., hurricanes).
8. Tidal marshes. Identification of high marsh (irregularly flooded) versus low marsh (regularly flooded) is conservative. Most
marshes were identified as high marsh and some low marsh may be included in this type.
9. Water regimes. These hydrologic characteristics were determined based on spectral signatures on the imagery coupled with
findings from limited field investigations. Long-term hydrologic studies would improve the results but were beyond the scope
of the NWI. On the coastal plain and glaciolacustrine plains, the “B” water regime (saturated) was applied to areas that are
seasonally saturated. Note: The earliest NWI mapping applied the temporarily flooded water regime to these wetlands, but it
was later felt that the saturated water regime would better reflect site wetness brought about by seasonal high water tables from
winter to early spring and not by inundation (i.e., ponding in micro-depressions).
10. Farmed wetlands. In the Northeast, the early NWI mapping tended to limit farmed wetlands to cultivated cranberry bogs
due to the ease of their identification. Later, the NWI also mapped depressional wetlands in cultivated fields as farmed wetlands
based on their appearance on aerial imagery. Overall, farmed wetlands are conservatively mapped by the NWI and the actual
acreage of such areas is greater than cited in this report. Determination of farmed wetlands in areas subject to drainage typically
would require a more detailed assessment of their hydrology for accurate identification.
11. Linear wetlands. Long, narrow wetlands that follow drainageways and stream corridors may or may not be mapped
depending on project objectives. Although the hardcopy NWI maps showed these areas, NWI’s online mapping tool - Wetlands
Mapper - does not display such features at this time.
12. Inclusion of uplands. Small upland features may be included within mapped wetland boundaries due to image scale. Field
inspections and analysis of more detailed imagery may be used to identify such features.
15
Wetlands of the Northeast: Results of the National Wetlands Inventory
The National Wetlands Database
The database used to generate the acreage summaries
for this report is maintained by the National Wetlands
Inventory’s National Support and Standards Team
(Madison, WI). Wetland geospatial data for this
report were entered into the national database prior to
September 2009. The data for Northeast wetlands were
produced exclusively by the Region’s NWI Program.4
Data summaries were generated from the polygonal
data in the database (no linear data were analyzed)
by GIS specialists at Virginia Tech’s Conservation
Management Institute (Blacksburg, VA). Data were
summarized for states, counties, and hydrologic units
(HUC-4 and HUC-8 units). Data presented in this
report refer only to the state totals (acreages of wetlands
and deepwater habitats by major type). Data for the
other groupings are available on a limited basis upon
request: contact Ralph Tiner at ralph_tiner@fws.gov. In
the future, these data may be posted online.
Aggregating Wetland Types for This Report
Due to the classification hierarchy that includes
system, subsystem, class, subclass, water regime, and
other modifiers, there are thousands of combinations
possible. To simplify the data for this report, data were
aggregated at the class level. In compiling this regional
summary, mixed classes were assigned to the dominant
class (e.g., PFO1/SS1C was included in the forested
wetland category - PFO, while PSS1/FO1C was placed in
scrub-shrub type - PSS). Marine, Estuarine, Lacustrine
and Palustrine wetlands can be readily identified by
the NWI code (i.e., M2___, E2___, L2___ and P____,
respectively). While some Riverine wetland types can
be clearly identified as wetland by consulting the class
level – unconsolidated shore, rocky shore, or streambed
(intermittent) – or by water regime (not permanently
flooded), open water Riverine wetlands are not easily
recognized since shallow water habitats are not
separated from deep water ones – all are classified either
rock bottom or unconsolidated bottom. Consequently,
all permanently flooded rivers and streams (rock
bottom and unconsolidated bottom) were placed in the
deepwater habitat category for these summaries. The
only exception to this was where the bottom type was
mixed with emergent wetland. The presence of this
vegetation suggests that the area is a shallow water
wetland. This was a rare occurrence. If the open water
area was mixed with aquatic bed vegetation, its acreage
was included in the deepwater habitat summaries since
such vegetation can grow in deep water or as a floating
mat in slow-flowing rivers and streams.
Interpretation of Results
The numbers presented in this report represent the
best available wetland acreage estimates for the areas
completed by the NWI as of September 2009. They
reflect the tabular results of 35-years of mapping by
the program (see Figure 7 for effective inventory date
based on imagery used). For coastal states, the marine
acreage does not reflect the full extent of state waters
as NWI data only go to the limits of the most seaward
U.S. Geological Survey topographic map. Statewide
NWI data are not complete for three states in the
region (Table 3). The numbers presented for New
York represent the findings for about three-quarters
of the state (i.e., digital wetland data). Although NWI
completed wetland mapping for Massachusetts and
Vermont, digital data for a few quads have not been
produced. The findings for these states, however,
represent more than 98 percent of the states. Readers
should refer to Figure 6 to see what parts of these three
states the summary data reflect. Farmed wetlands are
not consistently mapped and in all states, the extent
of farmed wetlands is probably larger than given in
this report. Another important point is that since data
are added to the database periodically, the acreage of
wetlands mapped will change overtime. For the latest
acreage, individuals may want to download NWI data
for a state and generate acreage summaries. For
information on updates since September 2009, contact
contact Ralph Tiner, Regional Wetland Coordinator at
ralph_tiner@fws.gov
4 The national database also includes FGDC-compliant wetland data produced by other organizations, but to date, there are no such data from
northeastern states. In the near future, however, the state of Delaware will be submitting such data for Kent and New Castle Counties.
16
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table 3. Type and coverage of NWI data for each Northeast state and the District of Columbia as of September 2009.
The number represents the % of area covered by the data type.
State
Digital
Data
Hardcopy
Maps Only
No
Data
Connecticut 100.0 -- --
Delaware 100.0 -- --
District of Columbia 100.0 -- --
Maine 100.0 -- --
Maryland 100.0 -- --
Massachusetts 98.0 2.0 --
New Hampshire 100.0 -- --
New Jersey 100.0 -- --
New York 73.9 9.7 16.4
Pennsylvania 100.0 -- --
Rhode Island 100.0 -- --
Vermont 99.2 0.8 --
Virginia 100.0 -- --
West Virginia 100.0 -- --
NWI Data Type
17
Wetlands of the Northeast: Results of the National Wetlands Inventory
Extent of Wetlands and Deepwater Habitats in the
Northeast
The results of the 35-year effort by the NWI are
summarized for the region in a series of tables and
Appendix D. The first two tables (Tables 4 and 5) give
wetland and deepwater totals according to ecological
system for each state and the District of Columbia.
Table 6 shows the percent of the state’s land area that
was occupied by wetland. Tables 7 and 8 address the
dominant types of tidal and palustrine wetlands across
the region. More detailed tabular summaries for each
state and the District of Columbia are given in Appendix
D. These tables include the acreage of specific types
of wetland and deepwater habitat mapped (to the class
level).
Note: Remember that NWI data were not complete for
three states: New York, Massachusetts, and Vermont,
so the results do not represent statewide totals (Table
3; Figure 6). For New York, digital NWI data were
available for 74 percent of the state. For Massachusetts
and Vermont, a few NWI maps were not digitized, so the
results for these states are based on 98 percent and 99
percent coverage, respectively.
Northeastern states with more than one-half million
acres of wetland were Maine (2.175M acres), New York
(1.573M acres for 73.9% of the state mapped by NWI),
Virginia (1.471M acres), New Jersey 0.937M acres),
Maryland (0.701M acres), and Massachusetts (0.536M
acres) (Table 4). Mountainous West Virginia and Rhode
Island, the smallest state in the nation, had the least
wetland acreage.
Five states had more than one million acres of deepwater
habitat mapped (Table 5). New York had the most
acreage due to the presence of Lake Ontario, Long
Island Sound, Peconic Bay, other coastal waters behind
its barrier islands (e.g., Jones Beach Island and Fire
Island), and marine waters offshore. Maine was second-ranked
and had the most marine acreage due to the Gulf
of Maine (e.g., Penobscot and Casco Bays), while Virginia
with the bulk of Chesapeake Bay was third-ranked.
Delaware had the highest density of wetland per land
area with 21 percent of the state represented by wetland
(Table 6). New Jersey was a close second with about 20
percent coverage by wetland. Other states with more
than 10 percent of their land area occupied by wetland
were Maryland, Maine, Massachusetts, and Rhode
Island.
The presence of Chesapeake Bay and its tidal wetlands
led to Virginia and Maryland being top-ranked in the
acreage of tidal wetlands (Table 7). Virginia was first-ranked
with over 444,000 acres mapped, while Maryland
possessed nearly 295,000 acres. New Jersey was third-ranked
with more than 250,000 acres of tidal wetlands,
followed by Maine with almost 168,000 acres. Estuarine
emergent wetlands (salt and brackish marshes) were
the predominant tidal wetland type in all coastal states
except Maine where estuarine unconsolidated shores
(tidal flats) were most common. Maine with its irregular
rocky shoreline had the most acreage of marine
wetlands, comprising about 65 percent of the entire
region’s marine wetlands (Table 4). Rocky shore and
unconsolidated wetlands were the predominant marine
wetland type in Maine, whereas unconsolidated shore
(intertidal beaches and tidal flats) was the most common
type in other states (Table 7).
Palustrine wetlands (freshwater marshes, swamps,
bogs, and ponds) were the most abundant general
wetland type in all states (Table 4). Maine had the
most palustrine wetland acreage with about 2 million
acres mapped, while New York and Virginia both had
over one million acres. When the NWI is completed
for New York that state might end up with the greatest
palustrine wetland acreage. Currently with 74 percent
of the state mapped, 1.5 million acres were reported
and if the acreage in the unmapped portion of the state
has at least the same wetland density as the rest of
the state, New York will have over 2 million acres and
slightly more than was mapped in Maine. Other states
with more than 400,000 acres of these wetlands were,
in order of abundance: New Jersey, Massachusetts,
Maryland, and Pennsylvania. Forested wetlands were
the dominant palustrine wetland type in all states, except
in West Virginia where unconsolidated bottoms (ponds)
were the most common type (Table 8). Maine had the
most acreage of forested and scrub-shrub wetlands
mapped with over one million acres and nearly 550,000
acres, respectively. New York was second-ranked in
both forested and scrub-shrub wetland acreage, in spite
of the fact that the data represent only 74 percent of
the state. Virginia was third-ranked in all categories
of palustrine vegetated wetlands and second-ranked in
pond acreage (unconsolidated bottom). New York had
the most acreage of both palustrine emergent wetlands,
unconsolidated bottom wetlands (ponds), and farmed
wetlands. New Jersey was second-ranked in farmed
wetlands due to the extent of cranberry cultivation,
followed by Massachusetts (another cranberry-producing
state) and Delaware.
18
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table 4. Wetland acreage for northeastern states and the District of Columbia based on NWI data as of September
2009. *Note that NWI digital data for New York covers 74% of the state; see Figure 6 for location of mapped area where
digital data are available.
Marine Estuarine Palustrine Lacustrine Riverine
Total
Wetlands Rank
Connecticut -- 18,788 181,286 1,513 292 201,879 11
Delaware 622 83,082 178,885 54 434 263,077 10
District of Columbia -- -- 237 27 149 413 14
Maine 69,816 83,175 2,000,893 16,495 4,753 2,175,132 1
Maryland 722 248,214 448,214 1,415 1,951 700,516 5
Massachusetts 21,269 61,854 450,114 2,974 168 536,379 6
New Hampshire 886 9,297 280,234 698 1,455 292,570 8
New Jersey 4,224 208,713 719,991 784 3,274 936,986 4
New York 4,983 36,161 1,485,846 39,637 6,126 1,572,753 2
Pennsylvania -- 55 420,118 8,809 3,665 432,647 7
Rhode Island 930 7,288 62,454 6 -- 70,678 12
Vermont -- -- 240,464 22,437 482 263,383 9
Virginia 4,377 350,189 1,108,015 4,393 3,738 1,470,712 3
West Virginia -- -- 54,406 2,550 1,442 58,398 13
Totsl 107,829 1,106,816 7,631,157 101,792 27,929 8,975,523
Acreage Summaries
19
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table 5. Deepwater habitat acreage for northeastern states and the District of Columbia based on NWI data as of
September 2009. *Note that NWI digital data for New York covers 74% of the state; see Figure 6 for mapped area
where digital data are available.
Marine Estuarine Lacustrine Riverine Total Rank
Connecticut -- 349,005 36,341 14,683 400,029 8
Delaware 54,873 271,779 4,176 4,249 335,077 9
District of Columbia -- -- 319 3,944 4,263 14
Maine 1,345,872 78,937 922,796 92,294 2,439,899 2
Maryland 57,415 1,541,510 20,956 38,633 1,658,514 4
Massachusetts 1,048,892 97,459 124,478 21,564 1,292,393 5
New Hampshire 42,842 7,711 166,859 19,677 237,089 12
New Jersey 308,601 508,179 50,594 26,670 894,044 6
New York 785,899 847,238 1,174,581 145,227 2,952,945 1
Pennsylvania -- 647 312,209 170,731 483,587 7
Rhode Island 172,630 88,390 19,484 1,079 281,583 10
Vermont -- -- 199,426 13,341 212,767 11
Virginia 258,673 1,362,007 139,669 146,736 1,907,085 3
West Virginia -- -- 17,089 91,012 108,101 13
Totsl 4,075,697 5,152,862 3,188,977 789,840 13,207,376
Acreage Summaries
Table 6. Percent of land area mapped as wetland by the NWI. Land area comes from U.S. Census 2000 data as reported
by Wikipedia.org. http://simple.wikipedia.org/wiki/List_of_U.S._states_by_area
Land Area
(sq. mi.)
%
Wetland Rank
Connecticut 4,845 6.5 8
Delaware 1,954 21.0 1
District of Columbia 61 1.1 13
Maine 30,862 11.0 4
Maryland 9,774 11.2 3
Massachusetts 7,840 10.9* 5
New Hampshire 8,968 5.1 10
New Jersey 7,417 19.7 2
New York 47,214 7.0* 7
Pennsylvania 44,817 1.5 12
Rhode Island 1,045 10.6 6
Vermont 9,250 4.5* 11
Virginia 39,594 5.8 9
West Virginia 24,078 0.4 14
*NWI digital data does not cover entire state; percent based on NWI acreage versus proportion of state mapped
(MA – 98.0%, NY – 73.9%, and VT – 99.2%).
20
Wetlands of the Northeast: Results of the National Wetlands Inventory
Marine Estuarine Palustrine (tidal) Riverine
US RS Other EM US
Other EM FO SS Other
EM/
US*
Tptal
Area Rank
Connecticut -- -- -- 12,128 6,393 267 1,225 50 349 45 251 20,708 8
Delaware 622 -- -- 77,256 4,880 946 3,229 5,520 1,550 715 434 95,152 5
District of Columbia -- -- -- -- -- -- 7 79 1 2 141 230 12
Maine 26,407 30,141 13,268 22,539 51,620 9,016 2,203 6,144 3,508 405 2,420 167,671 4
Maryland 722 -- -- 205,184 23,670 19,360 3,955 39,960 2,926 250 1,750 294,777 2
Massachusetts 19,488 825 956 44,894 15,501 1,459 1,182 1,808 1,483 352 6 87,954 6
New Hampshire 500 161 225 5,904 3,273 120 110 520 164 60 -- 11,037 9
New Jersey 4,224 12 -- 201,837 5,154 1,722 10,557 18,870 10,584 890 2,731 256,569 3
New York 4,957 18 8 27,684 7,074 1,403 1,558 2,570 499 230 440 46,441 7
Pennsylvania -- -- -- -- 55 -- 200 220 13 46 917 1,451 11
Rhode Island 714 215 1 3,678 3,419 191 34 94 16 33 -- 8,395 10
Virginia 4,285 -- 92 197,335 143,789 9,065 21,839 56,238 8,123 771 2,547 444,084 1
Table 7. Acreage of major tidal wetland types across the region. Note: Freshwater tidal wetlands are represented by Palustrine and Riverine types.
Coding: US – Unconsolidated Shore, RS – Rocky Shore, EM – Emergent, FO – Forested, SS – Scrub-Shrub.
*Acreage is mostly emergent and unconsolidated shore wetland but may include a few acres of minor types (see state tables in Appendix D for details).
21
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table 8. Acreage of major palustrine wetland types across the region. Note: Includes freshwater tidal palustrine wetlands.
Emergent Forested Scrub-Shrub
Unconsolidated
Bottom Other Total Rank
Connecticut 12,613 106,463 27,818 34,135 257 181,286 10
Delaware 11,805 146,412 13,163 3,780 3,725* 178,885 11
District of Columbia 12 183 9 23 10 237 14
Maine 200,952 1,194,848 547,999 55,658 1,436* 2,000,893 1
Maryland 33,958 359,897 35,932 16,649 1,778* 448,214 6
Massachusetts 39,682 293,268 84,562 26,983 5,619* 450,114 5
New Hampshire 39,452 140,451 73,984 26,101 246 280,234 8
New Jersey 67,314 515,951 102,610 27,782 6,334* 719,991 4
New York 219,944 892,019 257,411 92,773 23,699* 1,485,846 2
Pennsylvania 59,023 219,101 79,589 60,452 1,953 420,118 7
Rhode Island 3,051 48,665 5,887 4,680 171* 62,454 12
Vermont 47,222 117,801 59,947 13,717 1,777* 240,464 9
Virginia 107,743 811,100 103,902 82,291 2,979* 1,108,015 3
West Virginia 13,623 12,762 11,198 16,486 337 54,406 13
*Includes farmed wetlands: 3,370 acres in DE, 491 acres in ME (including 307 acres of cultivated cranberry bogs), 662 acres in MD, 4,528 acres in MA
(including 4,473 acres of cranberry bogs), 7,401 acres in NJ (including 4,590 acres of cranberry bogs), 21,731 acres in NY, 107 acres in RI (cranberry
bogs), 1,114 acres in VT, and 1,171 acres in VA.
22
Wetlands of the Northeast: Results of the National Wetlands Inventory
Summary
Since the mid-1970s, the U.S. Fish and Wildlife Service’s NWI Program has completed at least one phase of
mapping for all northeastern states, except New York. Most of the region has NWI data in digital form that allowed
generation of acreage summaries of the NWI findings for each state and the District of Columbia. To date, nearly 9
million acres of wetlands have been mapped and included in the NWI digital database. Three states had more than
one million acres of wetlands recorded: Maine (2.175M acres), New York (1.573M acres with only 74% of the state
completed), and Virginia (1.471M acres). Wetland density (wetland acres/unit area) was highest in states dominated
by the coastal plain - Delaware had the highest density of wetland with 21 percent of the state covered by wetland,
followed closely by New Jersey with 20 percent. Virginia and Maryland, the Chesapeake Bay states, had the most
tidal wetland acreage, followed by New Jersey. Estuarine emergent wetlands (salt and brackish marshes) were the
dominant tidal wetland type across the region, whereas forested wetlands dominated freshwater environments.
In addition to creating NWI maps and geospatial data, the Region’s NWI Program has produced a variety of other
products including multi-state wetland trends analysis reports, inventory of wetland change reports, watershed-based
wetland characterizations and preliminary functional assessments, and inventories of potential wetland
restoration sites. These products plus the digital geospatial data and accompanying status reports have greatly
increased our knowledge of the extent, distribution, and diversity of wetlands, their status and trends, wetland
functions, and opportunities for their restoration. As such, the NWI has provided vital information to various
Service programs, other federal agencies, state agencies, and others that has been used to help protect, conserve,
and restore our nation’s wetlands.
23
Wetlands of the Northeast: Results of the National Wetlands Inventory
References
Bailey, R.G. 1994. Ecoregions of the United States. U.S.D.A. Forest Service, Washington, DC. Map (scale
1:7,500,000). Revised. http://www.fs.fed.us/rm/ecoregions/products/map-ecoregions-united-states/
Ciminelli, J. and J. Scrivani. 2007. Virginia Conservation Lands Needs Assessment: Virginia Watershed Integrity
Model. Virginia Department of Conservation and Recreation-Division of Natural Heritage, Virginia Department
of Forestry, Virginia Commonwealth University-Center for Environmental Studies, and Virginia Department
of Environmental Quality-Coastal Zone Management Program. http://www.dcr.virginia.gov/natural_heritage/
vclnawater.shtml
Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of Wetlands and Deepwater Habitats of
the United States. U.S. Fish and Wildlife Service, Washington, DC. FWS-OBS/79-61. http://library.fws.gov/FWS-OBS/
79_31.pdf
Dahl, T.E. 2006. Status and Trends of Wetlands in the Conterminous United States 1998 to 2004. U.S. Department
of the Interior, Fish and Wildlife Service, Washington, DC. http://www.fws.gov/wetlands/_documents/gSandT/
NationalReports/StatusTrendsWetlandsConterminousUS1998to2004.pdf
FGDC Wetlands Subcommittee. 2009. Wetland Mapping Standard. Federal Geographic Data Committee Document
Number FGDC-STD-015-2009. http://www.fws.gov/wetlands/_documents/gNSDI/FGDCWetlandsMappingStandard.
pdf
Frayer, W.E., T.J. Monahan, D.C. Bowden, and F.A. Graybill. 1983. Status and Trends of Wetlands and Deepwater
Habitats in the Conterminous United States 1950’s to 1970’s. Department of Forest and Wood Sciences, Colorado
State University, Ft. Collins, CO.
Tiner, R.W. (ed.). 2009. Status Report for the National Wetlands Inventory Program: 2009. U.S. Fish and Wildlife
Service, Division of Habitat and Resource Conservation, Branch of Resource and Mapping Support, Washington,
DC. http://www.fws.gov/wetlands/_documents/gOther/StatusReportNWIProgram2009.pdf
Tiner, R.W. 2005. In Search of Swampland: A Wetland Sourcebook and Field Guide. Revised and Expanded 2nd
Edition. Rutgers University Press, New Brunswick, NJ.
Tiner, R.W. 2003a. Dichotomous Keys and Mapping Codes for Wetland Landscape Position, Landform, Water Flow
Path, and Waterbody Type Descriptors. U.S. Fish and Wildlife Service, Northeast Region, Hadley, MA. http://
library.fws.gov/Wetlands/dichotomouskeys0903.pdf
Tiner, R.W. 2003b. Correlating Enhanced National Wetlands Inventory Data With Wetland Functions for Watershed
Assessments: A Rationale for Northeastern U.S. Wetlands. U.S. Fish and Wildlife Service, Northeast Region,
Hadley, MA. http://library.fws.gov/Wetlands/corelate_wetlandsNE.pdf
Tiner, R.W. 2004. Remotely-sensed indicators for monitoring the general condition of “natural habitat” in
watersheds: an application for Delaware’s Nanticoke River watershed. Ecological Indicators 4: 227-243. http://
wetlands.fws.gov/Pubs_Reports/EcologicalIndicatorsTiner.pdf
Tiner, R.W. 1999. Wetland Indicators. A Guide to Wetland Identification, Delineation, Classification, and Mapping.
Lewis Publishers, CRC Press, Boca Raton, FL.
Tiner, R.W. 1984. Wetlands of the United States: Current Status and Recent Trends. U.S. Department of
the Interior, Fish and Wildlife Service, Washington, DC. http://www.fws.gov/wetlands/_documents/gSandT/
NationalReports/WetlandsUSCurrentStatusRecentTrends1984.pdf
Tiner, R.W. and H.C. Bergquist. 2007. The Hackensack River Watershed, New Jersey/New York Wetland
Characterization, Preliminary Assessment of Wetland Functions, and Remotely-sensed Assessment of Natural
Habitat Integrity. U.S. Fish and Wildlife Service, National Wetlands Inventory, Ecological Services, Region 5,
Hadley, MA. http://library.fws.gov/Wetlands/HackensackRiverWatershed07.pdf
24
Wetlands of the Northeast: Results of the National Wetlands Inventory
Tiner, R.W., Jr., and J.T. Finn. 1986. Status and Recent Trends of Wetlands in Five Mid-Atlantic States: Delaware,
Maryland, Pennsylvania, Virginia, and West Virginia. U.S. Fish and Wildlife Service, Region 5, National Wetlands
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PA. Cooperative publication. http://www.fws.gov/wetlands/_documents/gSandT/StateRegionalReports/
StatusRecentTrendsWetlandsFiveMidAtlanticStates.pdf
Vance, L.K., K. Newlon, J. Clarke, and D.M. Stagliano. 2009. Assessment of Red Rock River Subbasin and Wetlands
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Natural Heritage Program, Helena, MT. http://mtnhp.org/Reports/BLM_2009.pdf
25
Wetlands of the Northeast: Results of the National Wetlands Inventory
APPENDIX A. LIST OF PRIMARY CONTRIBUTORS
TO THE NWI FOR THE NORTHEAST
The following agencies have contributed to the Region’s NWI Program by providing funding to support wetland
mapping or other products or have contributed to the NWI Program by performing photointerpretation/image
analysis or distributing NWI maps.
Federal Agencies
Army Corps of Engineers, New England, New York, Philadelphia, and Buffalo Districts
Natural Resource Conservation Service, Maine
Fish and Wildlife Service, Region 5 Refuges Program
Environmental Protection Agency, Regions 1, 2, and 3
Department of Defense
State Agencies
Connecticut Department of Environmental Protection
Delaware Department of Natural Resources and Environmental Control
Maine Geological Survey*
Maine Office of GIS
Maine State Planning Office
Maine Land Use Regulation Commission
Maryland Department of Natural Resources
Maryland Geological Survey*
Massachusetts Executive Office of Environmental Affairs
New Hampshire Office of State Planning*
New Jersey Department of Environmental Protection
New York Department of Environmental Conservation
Pennsylvania Department of Environmental Protection
Rhode Island Department of Environmental Management
Vermont Department of Environmental Conservation*
Virginia Department of Conservation and Recreation
West Virginia Division of Natural Resources
Local Governments
Kent County Conservation District (DE)
New York City Department of Environmental Protection (NY)
Suffolk County (NY)
Tompkins County (NY)
Ulster County (NY)
Universities
Cornell University*
University of Massachusetts*#
Virginia Polytechnic Institute and State University (Virginia Tech) #
*Map distribution centers
#Photointerpretation, image analysis, and data compilation
26
Wetlands of the Northeast: Results of the National Wetlands Inventory
APPENDIX B. OVERVIEW OF THE SERVICE’S
WETLAND CLASSIFICATION SYSTEM
The following section represents a simplified overview
of the Service's wetland classification system.
Consequently, some of the more technical points have
been omitted from this discussion. When actually
classifying a wetland, the reader is advised to refer to
the official classification document (Cowardin et al. 1979;
http://library.fws.gov/FWS-OBS/79_31.pdf) and should
not rely solely on this overview.
Overview of the Service’s Wetland Classification System
The Service's wetland classification system is hierarchial
or vertical in nature proceeding from general to
specific. In this approach, wetlands are first defined at a
rather broad level the SYSTEM. The term SYSTEM
represents "a complex of wetlands and deepwater
habitats that share the influence of similar hydrologic,
geomorphologic, chemical, or biological factors." Five
systems are defined: Marine, Estuarine, Riverine,
Lacustrine, and Palustrine. The Marine System
generally consists of the open ocean and its associated
high energy coastline, while the Estuarine System
encompasses salt and brackish marshes, nonvegetated
tidal shores, and brackish waters of coastal rivers and
embayments. Freshwater wetlands and deepwater
habitats fall into one of the other three systems:
Riverine (rivers and streams), Lacustrine (lakes,
reservoirs and large ponds), or Palustrine (e.g., marshes,
bogs, swamps and small shallow ponds). Thus, at the
most general level, wetlands can be defined as either
Marine, Estuarine, Riverine, Lacustrine or Palustrine.
Each system, with the exception of the Palustrine,
is further subdivided into SUBSYSTEMS. The
Marine and Estuarine Systems both have the same
two subsystems, which are defined by tidal water
levels: (1) Subtidal continuously submerged areas
and (2) Intertidal areas alternately flooded by tides
and exposed to air. Similarly, the Lacustrine System
is separated into two systems based on water depth:
(1) Littoral wetlands extending from the lake shore
to a depth of 6.6 feet (2 m) below low water or to the
extent of nonpersistent emergents (e.g., arrowheads,
pickerelweed, or spatterdock) if they grow beyond
that depth, and (2) Limnetic deepwater habitats lying
beyond the 6.6 feet (2 m) at low water. By contrast, the
Riverine System is further defined by four subsystems
that represent different reaches of a flowing freshwater
or lotic system: (1) Tidal water levels subject to tidal
fluctuations for at least part of the growing season,
(2) Lower Perennial permanent, flowing waters
with a well developed floodplain, (3) Upper Perennial
permanent, flowing water with very little or no floodplain
development, and (4) Intermittent channel containing
nontidal flowing water for only part of the year.
The next level - CLASS - describes the general
appearance of the wetland or deepwater habitat in terms
of the dominant vegetative life form or the nature and
composition of the substrate, where vegetative cover
is less than 30% (Table B-1). Of the 11 classes, five
refer to areas where vegetation covers 30% or more
of the surface: Aquatic Bed, Moss Lichen Wetland,
Emergent Wetland, Scrub Shrub Wetland and Forested
Wetland. The remaining six classes represent areas
generally lacking vegetation, where the composition
of the substrate and degree of flooding distinguish
classes: Rock Bottom, Unconsolidated Bottom, Reef
(sedentary invertebrate colony), Streambed, Rocky
Shore, and Unconsolidated Shore. Permanently flooded
nonvegetated areas are classified as either Rock Bottom
or Unconsolidated Bottom, while exposed areas are
typed as Streambed, Rocky Shore, or Unconsolidated
Shore. Invertebrate reefs are found in both
permanently flooded and exposed areas.
Each class is further divided into SUBCLASSES to
better define the type of substrate in nonvegetated
areas (e.g., bedrock, rubble, cobble gravel, mud, sand,
and organic) or the type of dominant vegetation (e.g.,
persistent or nonpersistent emergents, moss, lichen, or
broad leaved deciduous, needle leaved deciduous, broad-leaved
evergreen, needle leaved evergreen and dead
woody plants). Below the subclass level, DOMINANCE
TYPE can be applied to specify the predominant plant or
animal in the wetland community.
To allow better description of a given wetland or
deepwater habitat in regard to hydrologic, chemical
and soil characteristics and to human impacts, the
classification system contains four types of specific
modifiers: (1) Water Regime, (2) Water Chemistry, (3)
Soil, and (4) Special. These modifiers may be applied to
class and lower levels of the classification hierarchy.
Water regime modifiers describe flooding or soil
saturation conditions and are divided into two main
groups: tidal and nontidal. Tidal water regimes are
used where water level fluctuations are largely driven
by oceanic tides. Tidal regimes can be subdivided into
two general categories, one for salt and brackish water
tidal areas and another for freshwater tidal areas. This
distinction is needed because of the special importance
of seasonal river overflow and ground water inflows in
freshwater tidal areas. By contrast, nontidal modifiers
define conditions where surface water runoff, ground
water discharge, and/or wind effects (i.e., lake seiches)
cause water level changes. Both tidal and nontidal water
regime modifiers are presented and briefly defined in
Table B-2.
Water chemistry modifiers are divided into two
categories which describe the water's salinity or
hydrogen ion concentration (pH): (1) salinity modifiers
and (2) pH modifiers. Like water regimes, salinity
modifiers have been further subdivided into two
27
Wetlands of the Northeast: Results of the National Wetlands Inventory
groups: halinity modifiers for tidal areas and salinity
modifiers for nontidal areas. Estuarine and marine
waters are dominated by sodium chloride, which is
gradually diluted by fresh water as one moves upstream
in coastal rivers. On the other hand, the salinity of
inland waters is dominated by four major cations (i.e.,
calcium, magnesium, sodium, and potassium) and three
major anions (i.e., carbonate, sulfate, and chloride).
Interactions between precipitation, surface runoff,
ground water flow, evaporation, and sometimes plant
evapotranspiration form inland salts which are most
common in arid and semiarid regions of the country.
Table B-3 shows ranges of halinity and salinity modifiers
which are a modification of the Venice System (Remane
and Schlieper 1971). The other set of water chemistry
modifiers are pH modifiers for identifying acid (pH<5.5),
circumneutral (5.5 7.4) and alkaline (pH>7.4) waters.
Some studies have shown a good correlation between
plant distribution and pH levels (Sjors 1950; Jeglum
1971). Moreover, pH can be used to distinguish between
mineral rich (e.g., fens) and mineral poor wetlands (e.g.,
bogs).
The third group of modifiers soil modifiers are
presented because the nature of the soil exerts strong
influences on plant growth and reproduction as well as
on the animals living in it. Two soil modifiers are given:
(1) mineral and (2) organic. In general, if a soil has 20%
or more organic matter by weight in the upper 16 inches,
it is considered an organic soil, whereas if it has less than
this amount, it is a mineral soil. For specific definitions,
please refer to Appendix D of the Service's classification
system (Cowardin et al. 1979) or to Soil Taxonomy (Soil
Survey Staff 1975).
The final set of modifiers special modifiers were
established to describe the activities of people or
beaver affecting wetlands and deepwater habitats.
These modifiers include: excavated, impounded (i.e., to
obstruct outflow of water), diked (i.e., to obstruct inflow
of water), partly drained, farmed, and artificial (i.e.,
materials deposited to create or modify a wetland or
deepwater habitat).
References
Cowardin, L.M., V. Carter, F.C. Golet and E.T. LaRoe. 1979. Classification of Wetlands and Deepwater Habitats of
the United States. U.S. Fish and Wildlife Service, Washington, DC. FWS/OBS 79/31. 103 pp.
Jeglum, J.K. 1971. Plant indicators of pH and water level in peat lands at Candle Lake, Saskatchewan. Can. J. Bot.
49: 1661 1676.
Remane, A. and C. Schlieper. 1971. Biology of Brackish Water. Wiley Interscience Division, John Wiley & Sons,
New York. 372 pp.
Sjors, H. 1950. On the relation between vegetation and electro¬lytes in north Swedish mire waters. Oikos 2: 241
258.
Soil Survey Staff. 1975. Soil Taxonomy. Department of Agriculture, Soil Conservation Service, Washington, DC.
Agriculture Handbook No. 436. 754 pp.
28
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table B-1. Classes and subclasses of wetlands and deepwater habitats (Cowardin et al. 1979).
Class Brief Description Subclasses
Rock Bottom Generally permanently flooded areas with bottom substrates
consisting of at least 75% stones and boulders and less than
30% vegetative cover.
Bedrock; Rubble
Unconsolidated Bottom Generally permanently flooded areas with bottom substrates
consisting of at least 25% particles smaller than stones and
less than 30% vegetative cover.
Cobble-gravel; Sand;
Mud; Organic
Aquatic Bed Generally permanently flooded areas vegetated by plants
growing principally on or below the water surface line.
Algal; Aquatic Moss;
Rooted Vascular;
Floating Vascular
Reef Ridge-like or mound-like structures formed by the
colonization and growth of sedentary invertebrates.
Coral; Mollusk; Worm
Streambed Channel whose bottom is completely dewatered at low
water periods.
Bedrock; Rubble; Cobble-gravel;
Sand; Mud; Organic;
Vegetated (pioneer)
Rocky Shore Wetlands characterized by bedrock, stones or boulders
with areal coverage of 75% or more and with less than 30%
coverage by vegetation.
Bedrock; Rubble
Unconsolidated Shore Wetlands having unconsolidated substrates with less
than 75% coverage by stone, boulders and bedrock and
less than 30% vegetative cover, except by pioneer plants.
Cobble-gravel; Sand;
Mud; Organic;
Vegetated (pioneer)
Moss-Lichen Wetland Wetlands dominated by mosses or lichens where other
plants have less than 30% coverage.
Moss; Lichen
Emergent Wetland Wetlands dominated by erect, rooted, herbaceous
hydrophytes.
Persistent; Nonpersistent
Scrub-Shrub Wetland Wetlands dominated by woody vegetation less than 20
feet (6 m) tall.
Broad-leaved Deciduous;
Needle-leaved Deciduous;
Needle-leaved Evergreen;
Dead
Forested Wetland Wetlands dominated by woody vegetation 20 feet (6 m)
or taller.
Broad-leaved Deciduous;
Needle-leaved Deciduous;
Broad-leaved Evergreen;
Needle-leaved Evergreen;
Dead
29
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table B-2. Water regime modifiers, both tidal and nontidal groups (Cowardin et al. 1979).
Group Type of Water Water Regime Definition
Tidal Saltwater Subtidal Permanently flooded tidal waters
and brackish areas
Irregularly exposed Exposed less often than daily by tides
Regularly flooded Daily tidal flooding and exposure to air
Irregularly flooded Flooded less often than daily and typically
exposed to air
Freshwater Permanently flooded-tidal Permanently flooded by tides and river or
exposed irregularly by tides
Semipermanently flooded-tidal
Flooded for most of the growing season by river
overflow but with tidal fluctuation in water levels
Regularly flooded Daily tidal flooding and exposure to air
Seasonally flooded-tidal Flooded irregularly by tides and seasonally by
river overflow
Temporarily flooded-tidal Flooded irregularly by tides and for brief periods
during growing season by river overflow
Nontidal Inland freshwater and saline
areas
Permanently flooded Flooded throughout the year in all years
Intermittently exposed Flooded year-round except during extreme
droughts
Semipermanently flooded Flooded throughout the growing season in most
years
Seasonally flooded Flooded for extended periods in growing season,
but surface water is usually absent by end of
growing season
Saturated Surface water is seldom present, but substrate is
saturated to the surface for most of the season
Temporarily flooded Flooded for only brief periods during growing
season, with water table usually well below
the soil surface for most of the season
30
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table B-2. Water regime modifiers, both tidal and nontidal groups (Cowardin et al. 1979). continued
Group Type of Water Water Regime Definition
Nontidal Inland freshwater and saline
areas
Intermittently flooded Substrate is usually exposed and only flooded
for variable periods without detectable seasonal
periodicity (not always wetland; may be upland in
some situations)
Artificially flooded Duration and amount of flooding is controlled by
means of pumps or siphons in combination with
dikes or dams
Table B-3. Salinity modifiers for coastal and inland areas (Cowardin et al. 1979).
Coastal
Modifiers5
Inland
Modifiers6
Salinity
(l)
Approximate
Specific
Conductance
(Mhos at 25o C)
Hyperhaline Hypersaline > 40 > 60,000
Euhaline Eusaline 30-40 45,000-60,000
Mixohaline
(Brackish)
Mixosaline7 0.5-30 800-45,000
Polyhaline Polysaline 18-30 30,000-45,000
Mesohaline Mesosaline 5-18 8,000-30,000
Oligohaline Oligosaline 0.5-5 800-8,000
Fresh Fresh < 0.5 < 800
5 Coastal modifiers are employed in the Marine and Estuarine Systems.
6 Inland modifiers are employed in the Riverine, Lacustrine and Palustrine Systems.
7 The term "brackish" should not be used for inland wetlands or deepwater habitats.
31
Wetlands of the Northeast: Results of the National Wetlands Inventory
APPENDIX C. LIST OF REGIONAL NWI
PUBLICATIONS
(Note: Publications are listed by major topic.)
The following is a list of publications produced by the U.S. Fish and Wildlife Service, Northeast Region. Publications
are arranged by general topics. Some of these reports are online publications posted on the NWI website (http://
wetlands.fws.gov), click on “documents search engine” then type in title of the publication in the “key words” block.
Some are online documents at the Service’s Conservation Library and direct links are given. All publications with
numbers in the margin can be obtained free of charge from: U.S, Fish and Wildlife Service, Ecological Services, 300
Westgate Center Drive, Hadley, MA 01035-9589. Your request can be mailed in or emailed to ralph_tiner@fws.gov.
On email, please note "publication order" in the subject block.
WETLAND DEFINITION, CLASSIFICATION, AND BASIC CONCEPTS
101 “Wetlands are Ecotones - Reality or Myth?”
102 “How wet is a wetland?”
103 “The concept of a hydrophyte for wetland identification” (BioScience)
104 “Classification of wetland ecosystems”
195 “A Clarification of the U.S. Fish and Wildlife Service's Wetland Definition”
Dichotomous Keys and Mapping Codes for Wetland Landscape Position, Landform, Water Flow
Path, and Waterbody Type Descriptors by R. Tiner. September 2003.
http://library.fws.gov/Wetlands/dichotomouskeys0903.pdf
167 “Technical Aspects of Wetlands: Wetland Definitions and Classifications in the United States” by
R. Tiner. 1997.
Geographically Isolated Wetlands: A Preliminary Assessment of Their Characteristics and Status
in Selected Areas of the United States2002. U.S. Fish and Wildlife Service, Northeast Region,
Hadley, MA. http://library.fws.gov/Wetlands/isolated.pdf
WETLAND AND RIPARIAN MAPPING
105 “The National Wetlands Inventory - The First Ten Years”
106 “Creating a National Georeferenced Wetland Database for Managing Wetlands in the United
States”
107 “Use of high-altitude aerial photography for inventorying forested wetlands in the United States”
108 NWI Maps Made Easy: A User's Guide to National Wetlands Inventory Maps of the Northeast
Region by G.S. Smith. 1991.
111 Comparison of Four Scales of Color Infrared Photography for Wetland Mapping in Maryland by
R.W. Tiner and G.S. Smith. 1992. U.S. Fish and Wildlife Service, Region 5, Newton Corner, MA.
National Wetlands Inventory Report. R5-92/03. 15 pp. plus tables.
An Investigation and Verification of Draft NWI Maps for Cape May County, New Jersey by U.S.
Fish and Wildlife Service, New Jersey Field Office. 1992. Available from: New Jersey Field Office,
U.S. Fish and Wildlife Service, 927 N. Main Street (Bldg. D-1), Pleasantville, NJ 08232.
158 Map Accuracy of National Wetlands Inventory Maps for Areas Subject to Maine Land Use
Regulation Commission Jurisdiction by C. Nichols. 1994.
32
Wetlands of the Northeast: Results of the National Wetlands Inventory
162 Assessment of Remote Sensing/GIS Technologies to Improve National Wetlands Inventory Maps
by B. Wilen and G. Smith. 1996. Proceedings: Sixth Biennial Forest Service Remote Sensing
Applications Conference, Denver, CO.
164 “Some Uses of National Wetlands Inventory Maps and Digital Map Data in the Northeast”.
166 “NWI Maps: What They Tell Us”.
170 “Adapting the NWI for Preliminary Assessment of Wetland Functions”, R.W. Tiner. 1997. In: The
Future of Wetland Assessment: Applying Science through the Hydrogeomorphic Assessment
Approach and Other Approaches. The Association of State Wetland Managers Institute for Wetland
Science and Public Policy.
171 “NWI Maps--Basic Information on the Nation's Wetlands”, Ralph Tiner. In: BioScience. May 1997.
172 “Piloting a More Descriptive NWI”, Ralph Tiner. In: National Wetlands Newsletter, Vol. 19(5).
September-October 1997.
WETLAND IDENTIFICATION - FIELD GUIDES
Field Guide to Nontidal Wetland Identification by R.W. Tiner, Jr. 1988. Maryland Department of
Natural Resources and U.S. Fish and Wildlife Service. Cooperative publication. 283 pp. + 198 color
plates. Full color reproductions are available for purchase from:. http://www.wetlanded.com
WETLAND DELINEATION - MANUALS/ARTICLES
189 An Overview of Wetland Identification and Delineation Techniques, with Recommendations
for Improvement by Ralph W. Tiner. 2000. Wetland Journal, Volume 12, Number 1, Winter 2000. P.O.
Box P, 201 Boundary Lane, St. Michaels, Maryland 21663, (410) 745-9620
“The Primary Indicators Method - A Practical Approach to Wetland Recognition and Delineation in
the United States” (Wetlands) http://library.fws.gov/Wetlands/TINER_WETLANDS13.pdf
113 “Using Plants as Indicators of Wetland” (Proceedings of The Academy of Natural Sciences of
Philadelphia)
114 “Wetland boundary delineation”
115 “Wetland delineation 1991”
116 “Technical issues regarding wetland delineation”
161 “Practical Considerations for Wetland Identification and Boundary Delineation”
HYDRIC SOILS
Hydric Soils of New England by R.W. Tiner, Jr. and P.L.M. Veneman. Revised edition June 1995. University
of Massachusetts Cooperative Extension, Bulletin C-183R, Amherst, MA. Available from: University of
Massachusetts Extension, Bulletin Center, Cottage A, Thatcher Way, Amherst, MA 01003.
http://www.umassextension.org/Merchant2/merchant.mv
WETLAND PLANT LISTS/HYDROPHYTES
Lists of Potential Hydrophytes for the United States: A Regional Review and Their Use in Wetland
Identification by R.W. Tiner. 2006. WETLANDS 26(2):624-634. Available online at: http://www.fws.gov/
wetlands/ (use documents search engine).
33
Wetlands of the Northeast: Results of the National Wetlands Inventory
WETLAND PLANT - SOIL CORRELATION STUDIES
Soil-Vegetation Correlations in the Connecticut River Floodplain of Western Massachusetts by Peter
Veneman and Ralph Tiner, September 1990, U.S Fish and Wildlife Service, Washington D.C. Biological
Report 90(6). http://library.fws.gov/BiologicalReports/BR_90_6.pdf
STATE WETLAND REPORTS
Wetlands of New Jersey by R.W. Tiner, Jr. 1985. U.S. Fish and Wildlife Service, Region 5, National Wetlands
Inventory Project, Newton Corner, MA. http://library.fws.gov/Wetlands/NJ_wetlands85.pdf
Wetlands of Delaware by R.W. Tiner, Jr. 1985. U.S. Fish and Wildlife Service, Region 5, National Wetlands
Inventory Project, Hadley, MA and Delaware Department of Natural Resources and Environmental
Control, Wetlands Section, Dover, DE. Cooperative publication.
Wetlands of Rhode Island by R.W. Tiner. 1989. U.S. Fish and Wildlife Service, Region 5, National Wetlands
Inventory Project, Newton Corner, MA. http://library.fws.gov/Wetlands/RI_wetlands89.pdf
Wetlands of Connecticut by K. Metzler and R.W. Tiner. 1991. Connecticut Department of Environmental
Protection, Hartford, CT. http://www.fws.gov/wetlands/_documents/gOther/WetlandsConnecticut.pdf
Wetlands of Maryland by R.W. Tiner and D.G. Burke. 1995. U.S. Fish and Wildlife Service, Ecological
Services, Region 5, Hadley, MA and Maryland Department of Natural Resources, Annapolis, MD.
Cooperative publication. http://library.fws.gov/Wetlands/MD_wetlands85.pdf
West Virginia's Wetlands. Uncommon, Valuable Wildlands by R.W. Tiner. 1996. U.S. Fish and Wildlife
Service, Ecological Services, Northeast Region, Hadley, MA. http://www.fws.gov/wetlands/_documents/
gOther/WestVirginiasWetlandsUncommonValuableWildlands.pdf
Current Status of West Virginia's Wetlands by R.W. Tiner. 1996. U.S. Fish and Wildlife Service, Hadley, MA.
http://www.fws.gov/wetlands/_documents/gOther/CurrentStatusWestVirginiasWetlands.pdf
Maine Wetlands and Waters by R.W. Tiner. 2007. U.S. Fish and Wildlife Service, National Wetlands
Inventory Program, Northeast Region, Hadley, MA. Available online at: http://library.fws.gov/Wetlands/
maine07.pdf
New Hampshire Wetlands and Waters by R.W. Tiner. 2007. U.S. Fish and Wildlife Service, National
Wetlands Inventory Program, Northeast Region, Hadley, MA. Available online at: http://library.fws.gov/
Wetlands/NH07.pdf
WETLAND STATUS AND TREND REPORTS (estimates of wetland change)
123 Recent Changes in Estuarine Wetlands of the Conterminous United States by R.W. Tiner. 1991.
Reprinted from "Coastal Wetlands", Coastal Zone '91 Conference-ASCE, Long Beach, CA. 10 pp.
Wetlands of the United States: Current Status and Recent Trends by R.W. Tiner, Jr. 1984. U.S.
Fish and Wildlife Service, National Wetlands Inventory. http://www.fws.gov/wetlands/_documents/
gSandT/NationalReports/WetlandsUSCurrentStatusRecentTrends1984.pdf
124 Status and Recent Trends of Wetlands in Five Mid-Atlantic States: Delaware, Maryland,
Pennsylvania, Virginia, and West Virginia by R.W. Tiner, Jr. and J.T. Finn. 1986.
http://www.fws.gov/wetlands/_documents/gSandT/StateRegionalReports/
StatusRecentTrendsWetlandsFiveMidAtlanticStates.pdf
INVENTORIES OF WETLAND CHANGE REPORTS
125 Current Status and Recent Trends in Wetlands in Central Connecticut by R.W. Tiner, J. Stone, and
J. Gookin. 1989.
34
Wetlands of the Northeast: Results of the National Wetlands Inventory
126 Recent Wetland Trends in Southeastern Massachusetts by R.W. Tiner, Jr. and W. Zinni, Jr. 1988.
127 Pennsylvania's Wetlands: Current Status and Recent Trends by R.W. Tiner. 1990.
128 Current Status and Recent Trends in Wetlands of the Lake Erie and Delaware Estuary Coastal
Zones of Pennsylvania (1986-1989) by G.S. Smith and R.W. Tiner. 1992.
129 Recent Wetland Trends in Anne Arundel County, Maryland (1981-82 to
1988-90) by R.W. Tiner and D.B. Foulis. 1992.
130 Wetland Trends in Prince Georges County, Maryland From 1981 to 1988-89 by R.W. Tiner and D.B.
Foulis. 1992.
131 Wetland Status and Trends for the Pleasant Valley Quadrangle, Dutchess County, New York (1958-
1988) by Ralph W. Tiner and Glenn S. Smith. 1993.
132 “Agricultural impacts on wetlands in the northeastern United States” by Ralph W. Tiner, Jr. 1988.
133 Status and Trends of Wetlands in Cape May County, New Jersey and Vicinity (1977 to 1991) by
G.S. Smith and R.W. Tiner. 1993.
134 Wetland Status and Trends in Selected Areas of Maryland's Piedmont Region (1980-81 to 1988-89)
by R.W. Tiner and D.B. Foulis. 1993.
135 Wetland Status and Trends in Selected Areas of Maryland's Fall Zone (1981-82 to 1988-89) by R.W.
Tiner and D.B. Foulis. 1993.
136 Wetland Trends in Selected Areas of the Western Shore Region of Maryland (1981 to 1988) by R.W.
Tiner and D.B. Foulis. 1993.
137 Wetland Trends for the North East Quadrangle in Maryland (1981 to 1988) by R.W. Tiner and D.B.
Foulis. 1993.
138 Wetland Trends for the Kent Island and Queenstown Quadrangles in Eastern Maryland (1982 to
1989) by R.W. Tiner and D.B. Foulis. 1993.
139 Wetland Trends for the DuBois and Falls Creek Quadrangles in Pennsylvania (1983 to 1988) by
R.W. Tiner and D.B. Foulis. 1993.
140 Wetland Trends in the Williamsport Area of Pennsylvania (1977 to 1988/90) by R.W. Tiner and D.B.
Foulis. 1993.
141 Wetland Trends for the Hazelton Quadrangle in Pennsylvania (1981 to 1987) by R.W. Tiner and
D.B. Foulis. 1993.
142 Wetland Trends in Selected Areas of the Greater Harrisburg Region of Pennsylvania (1983-84 to
1987-88) by R.W. Tiner and D.B. Foulis. 1993.
143 Wetland Trends for Selected Areas of the Northeast Glaciated Region of Pennsylvania (1981-82 to
1987-88) by R.W. Tiner, D.B. Foulis, and T.W. Nuerminger. 1994.
144 Wetland Trends for Selected Areas of Dorchester County, Maryland and Vicinity (1981-82 to 1988-
89) by R.W. Tiner and D.B. Foulis. 1994.
144a Wetland Trends in Dorchester County, Maryland (1981-82 to 1988-89) by D.B. Foulis, T.W.
Nuerminger, and R.W. Tiner. 1995.
145 Wetland Trends for Selected Areas of the Lower Eastern Shore of the Delmarva Peninsula (1982 to
1988-89) by R.W. Tiner and D.B. Foulis. 1994.
146 Wetland Trends in Selected Areas of the Norfolk/Hampton Region of Virginia (1982 to 1989-90) by
R.W. Tiner and D.B. Foulis. 1994.
35
Wetlands of the Northeast: Results of the National Wetlands Inventory
147 Wetland Trends for Selected Areas in Northern Virginia (1980-81 to 1988/91) by R.W. Tiner and
D.B. Foulis. 1994.
148 Wetland Trends for Selected Areas of the Chickahominy River Watershed of Virginia (1982/84 to
1989-90) by R.W. Tiner and D.B. Foulis. 1994.
Recent Wetland Status and Trends in the Chesapeake Watershed (1982 to 1989): Technical Report
by R.W. Tiner, I. Kenenski, T. Nuerminger, D.B. Foulis, J. Eaton, G.S. Smith, and W.E.
Frayer. 1994. Chesapeake Bay Program, Annapolis, MD. http://www.fws.gov/wetlands/_documents/
gSandT/StateRegionalReports/RecentWetlandStatusTrendsChesapeakeWatershed1982to1989.pdf
149 Recent Wetland Status and Trends in the Chesapeake Watershed (1982 to 1989): Executive
Summary Report by R.W. Tiner. 1994.
150 Wetland Trends for Selected Areas of the Casco Bay Estuary of the Gulf of Maine (1974-77 to 1984-
87) by D.B. Foulis and R.W. Tiner. 1994.
151 Wetland Trends for Selected Areas of the Cobscook Bay/St. Croix River Estuary of the Gulf of
Maine (1975/77 to 1983-85) by D.B. Foulis and R.W. Tiner. 1994.
152 Wetland Trends for Selected Areas of the Coast of Massachusetts, from Plum Island to Scituate
(1977 to 1985-86) by D.B. Foulis and R.W. Tiner. 1994.
153 Wetland Trends for Selected Areas of the Gulf of Maine, from York, Maine to Rowley,
Massachusetts (1977 to 1985-86) by D.B. Foulis, J.A. Eaton, and R.W. Tiner. 1994.
154 Wetland Status and Trends in Charles County, Maryland (1981 to 1988-89) by D.B. Foulis and R.W.
Tiner. 1994.
155 Wetland Status and Trends in St. Marys County, Maryland (1981-82 to 1988-89) by D.B. Foulis
and R.W. Tiner. 1994.
156 Wetland Status and Trends in Calvert County, Maryland (1981-82 to 1988-89) by D.B. Foulis and
R.W. Tiner. 1994.
168 New York Tidal Wetland Trends: Pilot Study in Shinnecock Bay Estuary and Recommendations
for Statewide Analysis by R.W. Tiner. 1987.
173 Current Status of West Virginia's Wetlands: Results of the National Wetlands Inventory by R.W.
Tiner. 1996.
Chesapeake Bay Wetlands: The Vital Link Between the Watershed and the Bay. 14 pp. booklet.
Available from: U.S. Fish and Wildlife Service, Chesapeake Bay Field Office, 177 Admiral Cochrane
Drive, Annapolis, MD 21401; (410) 573-4583.
177 Wetland Status and Recent Trends for the Neponset Watershed, Massachusetts (1977-1991) by
R.W. Tiner, D.B. Foulis, C. Nichols, S. Schaller, D. Petersen, K. Andersen, and John Swords. 1998.
Delaware’s Wetlands: Status and Recent Trends by R.W. Tiner. June 2001. http://www.fws.gov/
wetlands/_documents/gSandT/StateRegionalReports/DelawaresWetlandsStatusRecentTrends.pdf
Wetland Status and Trends for the Hackensack Meadowlands: An Assessment Report from the
National Wetlands Inventory Program by R.W. Tiner, J.Q. Swords, and B.J. McClain. 2002.
http://library.fws.gov/wetlands/hackensack.pdf.
Coastal Wetland Trends in the Narragansett Bay Estuary During the 20th Century by R.W. Tiner,
I.J. Huber, T. Nuerminger, and A.L. Mandeville. 2004. http://library.fws.gov/Wetlands/
narragansett04.pdf
Recent Wetland Trends in Southeastern Virginia: 1994-2000. by R.W. Tiner, J.Q. Swords, and
H.C. Bergquist. 2005. http://library.fws.gov/Wetlands/sevirginia05.pdf
36
Wetlands of the Northeast: Results of the National Wetlands Inventory
100 Years of Estuarine Marsh Trends (1893 to 1995): Boston Harbor, Cape Cod, Nantucket,
Martha’s Vineyard, and the Elizabeth Islands by B.K. Carlisle, R.W. Tiner, M. Carullo, I. J. Huber,
T. Nuerminger, C. Polzen, and M. Shaffer. 2006. http://www.mass.gov/czm/estuarine_marsh_
trend1.htm
Mid-Atlantic Wetlands: A Disappearing Natural Treasure by R.W. Tiner. 1987.
http://library.fws.gov/Wetlands/midatlantic.pdf
Salt Marsh Trends in Selected Estuaries in Southwestern Connecticut by R.W. Tiner and others.
2006. http://library.fws.gov/wetlands/saltmarsh_ct06.pdf
INVENTORY REPORTS/ARTICLES
182 Wetland Trends in the Croton Watershed, New York (1968-1994) by R. Tiner, J. Swords, and S.
Schaller. 1999.
183 Wetland Trends in Delaware: 1981/2 to 1992 by R. Tiner, J. Swords, and S. Schaller. 1999.
192 The Peconic Watershed: Recent Trends in Wetlands and their Buffers. R.W. Tiner and others. 2000.
201 Geographically Isolated Wetlands of the United States by R.W. Tiner, U. S. Fish and Wildlife
Service. Also in Wetlands, Vol 23, No.3, Sept. 2003, pp 494-516, The Society of Wetland Scientists
202 Estimated Extent of Geographically Isolated Wetlands in Selected Areas of the United States
by Ralph Tiner, U.S. Fish and Wildlife Service. In Wetlands, Vol 23, No.3, Sept. 2003, pp 636-652,
The Society of Wetland Scientists
OTHER REGIONAL WETLAND INVENTORY REPORTS/ARTICLES
117 Preliminary NWI Wetland Acreage Reports for Massachusetts (1992) and Vermont (1987) by R. W.
Tiner, U.S. Fish and Wildlife Service, NWI Project, Newton Corner, MA
118 Wetlands Inventory of the FAA Technical Center, Atlantic City International Airport, New Jersey
by Ralph W. Tiner and Glenn S. Smith. 1993.
119 "Vascular plant communities in wetlands of Pennsylvania"
120 "Current status and recent trends in Pennsylvania's wetlands"
121 "Wetlands of the Delaware River Basin"
The Wetlands of Acadia National Park and Vicinity. A joint publication of the Department of
Wildlife Ecology, University of Maine; the Maine Agricultural and Forest Experiment Station; the
National Park Service; and the U.S. Fish and Wildlife Service. 1994. Miscellaneous Publication
721. Available from: Publications Office, Room 1, Maine Agricultural and Forest Expt. Station, 5782
Winslow Hall, University of Maine, Orono, ME 04469-5782; (207) 581-1110.
174 Wetlands in the Watersheds of the New York Water Supply System. R.W. Tiner. 1997. 17 pp. color
booklet. Limited copies through U.S. Fish and Wildlife Service. Available from: Laurie Machung,
New York City Department of Environmental Protection, Watershed Office of Public Affairs, 71
Smith Avenue, Kingston, NY 12401; (845) 340-7524.
Mid Atlantic Wetlands - A Disappearing Natural Treasure. R.W. Tiner, Jr., June 1987.
http://library.fws.gov/Wetlands/midatlantic.pdf
Wetlands of Saratoga County, New York. R. Tiner. 2000. 20 pp. color booklet. A Cooperative
National Wetlands Inventory Report. http://www.fws.gov/wetlands/_documents/gOther/
WetlandsSaratogaCounty.pdf
37
Wetlands of the Northeast: Results of the National Wetlands Inventory
Wetlands of Staten Island, New York. R. Tiner. 2000. 20 pp. color booklet. A Cooperative National
Wetlands Inventory Report. http://www.fws.gov/wetlands/_documents/gOther/
WetlandsStatenIsland.pdf
180 Wetlands and Deepwater Habitats at Saratoga County, New York; The Results of the National
Wetlands Inventory, by R.W. Tiner, I.K. Huber, D.B. Foulis, T. Nuerminger, G.S. Smith and M. J.
Starr. 2000.
Geographically Isolated Wetlands: A Preliminary Assessment of Their Characteristics and Status
in Selected Areas of the United States 2002. U.S. Fish and Wildlife Service, Northeast Region,
Hadley, MA. http://www.fws.gov/wetlands/_documents/gOther/GeographicallyIsolatedWetlandsFS.
pdf
Wetlands of the Boston Harbor Islands National Recreation Area by R. W. Tiner, J. Q. Swords,
and H.C. Bergquist. 2003. U.S. Fish and Wildlife Service, Northeast Region, Hadley, MA.
http://library.fws.gov/wetlands/boston_harbor03.pdf.
SUBMERGED AQUATIC VEGETATION SURVEYS
Eelgrass Survey for Eastern Long Island Sound, Connecticut and New York. R. Tiner, H. Bergquist, T.
Halavick, and A. MacLachlan. 2003.
2006 Eelgrass Survey for Eastern Long Island Sound, Connecticut and New York. R. Tiner, H.
Bergquist, T. Halavick, and A. MacLachlan. 2007. http://library.fws.gov/Wetlands/eelgrass_report_2006.pdf
An Inventory of Submerged Aquatic Vegetation and Hardened Shorelines of the Peconic Estuary, New York
by R.W. Tiner and others. 2003. http://library.fws.gov/Wetlands/peconic03.pdf
WETLAND RESTORATION AND CREATION (INCLUDING STREAM BUFFERS)
175 Wetland Restoration and Creation by R.W. Tiner. 1995.
Managing Common Reed (Phragmites australis) in Massachusetts: An Introduction to the Species
and Control Techniques by R. Tiner. 1998. http//www.massaudubon.org/Kids/Lively_Lessons/
Saltmarsh/restoration.html
187 Restoring Wetland and Streamside/Riparian Buffers by R.W. Tiner. 2003.
WETLAND MONITORING
179 Wetland Monitoring Guidelines: Operational Draft. U.S. Fish and Wildlife Service, Region 5,
Hadley, MA.
WETLAND EVALUATION/ASSESSMENT
Correlating Enhanced National Wetlands Inventory Data with Wetland Functions for Watershed
Assessments: A Rationale for Northeastern U.S. Wetlands by R. Tiner, October 2003. http://wetlands.fws.
gov/Pubs_Reports/HGMReportOctober2003.pdf
WATERSHED-BASED WETLAND STUDIES: CHARACTERIZATION AND PRELIMINARY FUNCTIONAL
ASSESSMENT, WETLAND RESTORATION, AND OVERALL ECOLOGICAL INTEGRITY
Historical Analysis of Wetlands and Their Functions for the Nanticoke River Watershed: A Comparison
Between Pre-settlement and 1998 Conditions. R. W. Tiner and H.C. Bergquist. 2003. http://library.fws.gov/
wetlands/Nanticoke04.pdf
38
Wetlands of the Northeast: Results of the National Wetlands Inventory
An Inventory of Coastal Wetlands, Potential Restoration Sites, Wetland Buffers, and Hardened Shorelines
for the Narragansett Bay Estuary: An Assessment Report from the National Wetlands Inventory Program.
R.W. Tiner and others. 2003. http://library.fws.gov/wetlands/RIcoast03.pdf
The Parker River Watershed: An Assessment of Recent Trends in Salt Marshes, Their Buffers, and River-
Stream Buffer Zones (1985-1999). 2002. http://library.fws.gov/wetlands/parkerriver02.pdf
Wetland Characterization and Preliminary Assessment of Wetland Functions for the Delaware and
Catskill Watersheds of the New York City Water Supply System. R.W. Tiner and J. Stewart. 2004.
Wetland Characterization and Preliminary Assessment of Wetland Functions for the Croton Watershed of
the New York City Water Supply System. R.W.Tiner, C.W. Polzen, and B. J. McClain. 2004.
Watershed-based Wetland Characterization for Maryland's Nanticoke River and Coastal Bays Watersheds:
A Preliminary Assessment Report. R.W. Tiner and others. 2000. http://www.fws.gov/wetlands/_documents/
gOther/WatershedbasedWetlandCharacterizationMarylandsNanticokeRiverWatershed.pdf
Watershed-based Wetland Characterizations for Delaware's Nanticoke River Watershed: A Preliminary
Assessment Report. R.W. Tiner and others. 2001. http://library.fws.gov/wetlands/DEnanticoke01.pdf
197 Enhancing Wetlands Inventory Data for Watershed-based Wetland Characterizations and
Preliminary Assessments of Wetland Functions. R.W. Tiner. 2002.
198 Remotely-sensed Natural Habitat Integrity Indices for Assessing the General Ecological
Condition of Watersheds. R.W. Tiner. 2002
Watershed-based Wetland Planning and Evaluation. A Collection of Papers from the Wetland
Millennium Event (August 6-12, 2000; Quebec City, Quebec, Canada). http://www.aswm.org/
propub/pubs/pdf/tiner_2002_wshed.pdf
180 Wetland Characterization Study and Preliminary Assessment of Wetland Functions for the Casco
Bay Watershed, Southern Maine. by R.W. Tiner and others. 1999. U.S. Fish and Wildlife Service,
Region 5, Hadley, MA.
185 Wetland Characterization and Preliminary Assessment of Wetland Functions for the Boyds
Corner and West Branch Sub-basins of the Croton Watershed, New York by R. Tiner, S. Schaller,
and M. Starr. 1999.
193 Wetlands and Potential Wetland Restoration Sites for the Mill Rivers and Manhan River
Watershed. R.W. Tiner and others. 2000
194 Wetlands and Potential Wetland Restoration Sites for the Shawsheen Watershed. R.W. Tiner and
others. 2000. (Cooperative USFWS and University of Massachusetts report)
Correlating Enhanced National Wetlands Inventory Data with Wetland Functions for Watershed
Assessments: A Rationale for Northeastern U.S. Wetlands by R. Tiner, October 2003. http://library.
fws.gov/Wetlands/corelate_wetlandsNE.pdf
Remotely-sensed indicators for monitoring the general condition of "natural habitat" in
watersheds: an application for Delaware's Nanticoke River watershed by R. Tiner. Published in
Ecological Indicators 4 (2004): 227-243. Contact ralph_tiner@fws.gov for copy.
205 Wetlands and Potential Wetland Restoration Sites for the Upper Ipswich Watershed.
WETLAND PROTECTION
201 Geographically Isolated Wetlands of the United States by R.W. Tiner, U. S. Fish and Wildlife
Service. Wetlands, Vol 23, No.3, Sept. 2003, pp. 494-516, The Society of Wetland Scientists.
39
Wetlands of the Northeast: Results of the National Wetlands Inventory
APPENDIX D. TABULUAR SUMMARIES OF NWI
FINDINGS FOR EACH STATE AND THE DISTRICT OF
COLUMBIA
(Note: Data are presented for each area alphabetically. Two tables are given: one for wetlands and the other for
deepwater habitat totals.)
Connecticut
Table CT-1. Acreage of wetlands for Connecticut based on NWI data in the national database as of September 2009
(see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Estuarine Intertidal Aquatic Bed
Emergent
Scrub-Shrub
Rocky Shore
Unconsolidated Shore
94
12,128
57
116
6,393
Total Estuarine 18,788
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Unconsolidated Bottom
Unconsolidated Shore
238
12,613 (1,225 = tidal)
106,463 (50 = tidal)
27,818 (349 = tidal)
1
34,135 (45 = tidal)
18
Total Palustrine 181,286 (1,669 = tidal)
Lacustrine Littoral Aquatic Bed
Emergent
Unconsolidated Bottom
Unconsolidated Shore
565
185
741
22
Total Lacustrine 1,513
Riverine Tidal Emergent
Unconsolidated Shore
(Subtotal)
167
84
(251)
Lower Perennial Rocky Shore
Unconsolidated Shore
(Subtotal)
16
24
(40)
Upper Perennial Unconsolidated Shore 1
Total Riverine 292
TOTAL MAPPED 201,879
40
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table CT-2. Acreage of deepwater habitats for Connecticut based on NWI data in the national database as of
September 2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Estuarine Subtidal Unconsolidated Bottom (UB) 349, 005
Total Estuarine 349,005
Lacustrine Limnetic Aquatic Bed (UB)
Unconsolidated Bottom
87
36,254
Total Lacustrine 36,341
Riverine Tidal Unconsolidated Bottom 7,356
Lower Perennial Rocky Shore
Unconsolidated Bottom
(Subtotal)
86
4,819
(4,905)
Upper Perennial Unconsolidated Bottom 2,422
Total Riverine 14,683
TOTAL MAPPED 400,029
41
Wetlands of the Northeast: Results of the National Wetlands Inventory
Delaware
Table DE-1. Acreage of wetlands for Delaware based on NWI data in the national database as of September 2009 (see
Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Unconsolidated Shore 622
Total Marine 622
Estuarine Intertidal Emergent
Forested
Scrub-Shrub
Unconsolidated Shore
77,256
11
935
4,880
Total Estuarine 83,082
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Unconsolidated Bottom
Unconsolidated Shore
14 (7 = tidal)
11,805 (3,229 = tidal)
146,412 (5,520 = tidal)
13,163 (1,550 = tidal)
3,370
3,780 (562 = tidal)
341 (146 = tidal)
Total Palustrine 178,885 (11,014 = tidal)
Lacustrine Littoral Emergent
Unconsolidated Bottom
12
42
Total Lacustrine 54
Riverine Tidal Emergent
Unconsolidated Shore
239
195
Total Riverine 434
TOTAL MAPPED 263,077
42
Wetlands of the Northeast: Results of the National Wetlands Inventory
System Subsystem Class Acreage
Marine Subtidal Unconsolidated Bottom 54,873
Total Marine 54,873
Estuarine Subtidal Unconsolidated Bottom 271,779
Total Estuarine 271,779
Lacustrine Limnetic Unconsolidated Bottom 4,176
Total Lacustrine 4,176
Riverine Tidal Unconsolidated Bottom 3,762
Lower Perennial Unconsolidated Bottom 487
Total Riverine 4,249
TOTAL MAPPED 335,077
Table DE-2. Acreage of deepwater habitats for Delaware based on NWI data in the national database as of September
2009 (see Figure 5 for locations and effective date of data based on imagery).
43
Wetlands of the Northeast: Results of the National Wetlands Inventory
District of Columbia
Table DC-1. Acreage of wetlands and deepwater habitats for District of Columbia, DC based on NWI data in the
national database as of September 2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Unconsolidated Bottom
Unconsolidated Shore
9
12 (7 = tidal)
183 (79 = tidal)
9 (1 = tidal)
23 (2 = tidal)
1
Total Palustrine 237 (89 = tidal)
Lacustrine Littoral Emergent
Unconsolidated Shore
26
1
Total Lacustrine 27
Riverine Tidal Emergent
Unconsolidated Shore
(Subtotal)
30
111
(141)
Lower Perennial Unconsolidated Shore 4
Upper Perennial Unconsolidated Shore 4
Total Riverine 149
TOTAL MAPPED 413
44
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table DC-2. Acreage of deepwater habitats for the District of Columbia based on NWI data in the national database as
of September 2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Lacustrine Limnetic Unconsolidated Bottom 319
Total Lacustrine 319
Riverine Tidal Unconsolidated Bottom 3,928
Upper Perennial Unconsolidated Bottom 16
Total Riverine 3.944
TOTAL MAPPED 4,263
45
Wetlands of the Northeast: Results of the National Wetlands Inventory
Maine
Table ME-1. Acreage of wetlands for Maine based on NWI data in the national database as of September 2009 (see
Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Aquatic Bed
Rocky Shore
Unconsolidated Shore
13,268
30,141
26,407
Total Marine 69,816
Estuarine Intertidal Aquatic Bed
Emergent
Scrub-Shrub
Rocky Shore
Streambed
Unconsolidated Shore
6,853
22,539
99
2,058
6
51,620
Total Estuarine 83,175
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Cultivated Cranberry Bog
Unconsolidated Bottom
Unconsolidated Shore
139
200,952 (2,203 = tidal)
1,194,848 (6,144 = tidal)
547,999 (3,508 = tidal)
184
307
55,658 (403 = tidal)
806 (2 = tidal)
Total Palustrine 2,000,893 (12,260 = tidal)
Lacustrine Littoral Aquatic Bed
Emergent
Rocky Shore
Unconsolidated Bottom
Unconsolidated Shore
115
260
7,950
458
7,712
Total Lacustrine 16,495
46
Wetlands of the Northeast: Results of the National Wetlands Inventory
Riverine Tidal Aquatic Bed
Emergent
Rocky Shore
Unconsolidated Shore
(Subtotal)
11
86
3
2,320
(2,420)
Lower Perennial Emergent
Rocky Shore
Unconsolidated Shore
(Subtotal)
13
38
1,185
(1,236)
Upper Perennial Rocky Shore
Unconsolidated Shore
(Subtotal)
13
1,083
(1,096)
Total Riverine 4,753
TOTAL MAPPED 2,175,132
47
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table ME-2. Acreage of deepwater habitats for Maine based on NWI data in the national database as of September
2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Subtidal Aquatic Bed
Unconsolidated Bottom
2,557
1,343,315
Total Marine 1,345,872
Estuarine Subtidal Aquatic Bed
Rock Bottom
Unconsolidated Bottom
12
13
78,922
Total Estuarine 78,937
Lacustrine Limnetic Aquatic Bed
Unconsolidated Bottom
14
922,782
Total Lacustrine 922,796
Riverine Tidal Rock Bottom
Unconsolidated Bottom
(Subtotal)
3
6,554
(6,557)
Lower Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
59
69,659
(69,718)
Upper Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
122
155,897
(16,019)
Total Riverine 92,294
TOTAL MAPPED 2,439,899
48
Wetlands of the Northeast: Results of the National Wetlands Inventory
Maryland
Table MD-1. Acreage of wetlands for Maryland based on NWI data in the national database as of September 2009 (see
Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Unconsolidated Shore 722
Total Marine 722
Estuarine Intertidal Emergent
Forested
Scrub-Shrub
Rocky Shore
Unconsolidated Shore
205,184
16,870
2,488
2
23,670
Total Estuarine 248,214
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Rock Bottom
Unconsolidated Bottom
Unconsolidated Shore
426
33,958 (3,955 = tidal)
359,897 (36,960 = tidal)
35,932 (2,926 = tidal)
662
140
16,649 (248 = tidal)
550 (2 = tidal)
Total Palustrine 448,214 (44,091 = tidal)
Lacustrine Littoral Aquatic Bed
Emergent
Rocky Shore
Unconsolidated Bottom
Unconsolidated Shore
6
535
8
139
727
Total Lacustrine 1,415
49
Wetlands of the Northeast: Results of the National Wetlands Inventory
Riverine Tidal Emergent
Unconsolidated Shore
(Subtotal)
1,574
176
(1,750)
Lower Perennial Emergent
Unconsolidated Shore
(Subtotal)
6
126
(132)
Upper Perennial Rocky Shore
Unconsolidated Shore
(Subtotal)
6
48
(54)
Unknown Perennial Rocky Shore
Unconsolidated Shore
(Subtotal)
4
11
(15)
Total Riverine 1,951
TOTAL MAPPED 700,516
50
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table MD-2. Acreage of deepwater habitats for Maryland based on NWI data in the national database as of September
2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Subtidal Unconsolidated Bottom 57,415
Total Marine 57,415
Estuarine Subtidal Aquatic Bed
Unconsolidated Bottom
2
1,541,508
Total Estuarine 1,541,510
Lacustrine Limnetic Unconsolidated Bottom 20,956
Total Lacustrine 20,956
Riverine Tidal Unconsolidated Bottom 17,100
Lower Perennial Unconsolidated Bottom 11,660
Upper Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
373
2,350
(2,723)
Unknown Perennial Unconsolidated Bottom 7,150
Total Riverine 38,633
TOTAL MAPPED 1,658,514
51
Wetlands of the Northeast: Results of the National Wetlands Inventory
Massachusetts
Table MA-1. Acreage of wetlands for Massachusetts based on NWI data in the national database as of September
2009. For this state, the data reflect acreage statistics for 98% of the state where NWI digital data are available (see
Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Aquatic Bed
Reef
Rocky Shore
Unconsolidated Shore
930
26
825
19,488
Total Marine 21,269
Estuarine Intertidal Aquatic Bed
Emergent
Forested
Scrub-Shrub
Reef
Rocky Shore
Unconsolidated Shore
254
44,894
2
1,009
64
130
15,501
Total Estuarine 61,854
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Cultivated Cranberry Bog
Unconsolidated Bottom
Unconsolidated Shore
684
39,682 (1,182 = tidal)
293,268 (1,808 = tidal)
84,562 (1,483 = tidal)
55
4,473
26,983 (328 = tidal)
407 (24 = tidal)
Total Palustrine 450,114 (4,825 = tidal)
Lacustrine Littoral Aquatic Bed
Emergent
Unconsolidated Bottom
Unconsolidated Shore
1,303
1,104
432
135
Total Lacustrine 2,974
52
Wetlands of the Northeast: Results of the National Wetlands Inventory
Riverine Tidal Emergent 6
Lower Perennial Rocky Shore
Unconsolidated Shore
(Subtotal)
7
65
(72)
Upper Perennial Unconsolidated Shore 21
Unknown Perennial Unconsolidated Shore 1
Intermittent Unconsolidated Shore 68
Total Riverine 168
TOTAL MAPPED 536,379
53
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table MA-2. Acreage of deepwater habitats for Massachusetts based on NWI data in the national database as of
September 2009. For this state, the data reflect acreage statistics for 98% of the state where NWI digital data are
available (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Subtidal Aquatic Bed
Unconsolidated Bottom
24,767
1,024,125
Total Marine 1,048,892
Estuarine Subtidal Aquatic Bed
Unconsolidated Bottom
7,624
89,835
Total Estuarine 97,459
Lacustrine Limnetic Aquatic Bed (AB)
Unconsolidated Bottom
Unconsolidated Bottom/AB
45
124,311
122
Total Lacustrine 124,478
Riverine Tidal Unconsolidated Bottom 951
Lower Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
7
17,244
(17,251)
Upper Perennial Unconsolidated Bottom 2,253
Unknown Perennial Unconsolidated Bottom 1,109
Total Riverine 21,564
TOTAL MAPPED 1,292,393
54
Wetlands of the Northeast: Results of the National Wetlands Inventory
New Hampshire
Table NH-1. Acreage of wetlands for New Hampshire based on NWI data in the national database as of September
2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Aquatic Bed
Rocky Shore
Unconsolidated Shore
225
161
500
Total Marine 886
Estuarine Intertidal Aquatic Bed
Emergent
Scrub-Shrub
Rocky Shore
Unconsolidated Shore
106
5,904
7
7
3,273
Total Estuarine 9,297
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Unconsolidated Bottom
Unconsolidated Shore
199
39,452 (110 = tidal)
140,451 (520 = tidal)
73,984 (164 = tidal)
1
26,101 (60 = tidal)
46
Total Palustrine 280,234 (854 = tidal)
Lacustrine Littoral Aquatic Bed
Emergent
Unconsolidated Bottom
Unconsolidated Shore
85
122
190
301
Total Lacustrine 698
Riverine Lower Perennial Unconsolidated Shore 713
Upper Perennial Rocky Shore
Unconsolidated Shore
(Subtotal)
6
701
(707)
Unknown Perennial Unconsolidated Shore 1
Intermittent Unconsolidated Shore 34
Total Riverine 1,455
TOTAL MAPPED 292,570
55
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table NH-2. Acreage of deepwater habitats for New Hampshire based on NWI data in the national database as of
September 2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Subtidal Unconsolidated Bottom 42,842
Total Marine 42,842
Estuarine Subtidal Unconsolidated Bottom (UB)
Aquatic Bed/UB
7,659
52
Total Estuarine 7,711
Lacustrine Limnetic Unconsolidated Bottom 166,859
Total Lacustrine 124,478
Riverine Tidal Unconsolidated Bottom 27
Lower Perennial Unconsolidated Bottom 17,867
Upper Perennial Unconsolidated Bottom 1,782
Unknown Perennial Unconsolidated Bottom 1
Total Riverine 19,677
TOTAL MAPPED 237,089
56
Wetlands of the Northeast: Results of the National Wetlands Inventory
New Jersey
Table NJ-1. Acreage of wetlands for New Jersey based on NWI data in the national database as of September 2009
(see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Rocky Shore
Unconsolidated Shore
12
4,212
Total Marine 4,224
Estuarine Intertidal Aquatic Bed
Emergent
Forested
Scrub-Shrub
Rocky Shore
Unconsolidated Shore
40
201,837
77
1,603
2
5,154
Total Estuarine 208,713
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Cultivated Cranberry Bog
Unconsolidated Bottom
Unconsolidated Shore
131 (17 = tidal)
67,314 (10,557 = tidal)
515,951 (18,870 = tidal)
102,610 (10,584 = tidal)
2,811
4,500
25,782 (757 = tidal)
802 (116 = tidal)
Total Palustrine 719,991 (40,901 = tidal)
Lacustrine Littoral Rock Bottom
Unconsolidated Bottom
Unconsolidated Shore
34
580
170
Total Lacustrine 784
Riverine Tidal Emergent
Unconsolidated Shore
(Subototal)
660
2,071
(2,731)
Lower Perennial Emergent
Unconsolidated Shore
(Subtotal)
57
49
(106)
Intermittent Streambed
Unconsolidated Shore
(Subtotal)
154
283
(437)
Total Riverine 3,274
TOTAL MAPPED 936,986
57
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table NJ-2. Acreage of deepwater habitats for New Jersey based on NWI data in the national database as of
September 2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Subtidal Unconsolidated Bottom 308,601
Total Marine 308,601
Estuarine Subtidal Unconsolidated Bottom 508,179
Total Estuarine 508,179
Lacustrine Limnetic Unconsolidated Bottom 50,594
Total Lacustrine 50,594
Riverine Tidal Unconsolidated Bottom 13,525
Lower Perennial Unconsolidated Bottom 12,371
Upper Perennial Rock Bottom
Unconsolidated Bottom
8
766
(774)
Total Riverine 26,670
TOTAL MAPPED 894,044
58
Wetlands of the Northeast: Results of the National Wetlands Inventory
New York
Table NY-1. Acreage of wetlands for New York based on NWI data in the national database as of September 2009. For
this state, the data reflect acreage statistics for 74% of the state where NWI digital data are available (see Figure 5 for
locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Aquatic Bed
Rocky Shore
Unconsolidated Shore
8
18
4,957
Total Marine 4,983
Estuarine Intertidal Aquatic Bed
Emergent
Forested
Scrub-Shrub
Rocky Shore
Unconsolidated Shore
249
27,684
8
1,077
69
7,074
Total Estuarine 36,161
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Unconsolidated Bottom
Unconsolidated Shore
1,208 (1 = tidal)
219,944 (1,558 = tidal)
892,019 (2,570 = tidal)
257,411 (499 = tidal)
21,731
92,773 (229 = tidal)
760
Total Palustrine 1,485,846 (4,857 = tidal)
Lacustrine Littoral Aquatic Bed
Emergent
Rocky Shore
Unconsolidated Bottom
Unconsolidated Shore
2,051
694
48
33,553
3,291
Total Lacustrine 39,637
59
Wetlands of the Northeast: Results of the National Wetlands Inventory
Riverine Tidal Aquatic Bed
Emergent
Unconsolidated Shore
(Subototal)
4
9
427
(440)
Lower Perennial Aquatic Bed
Emergent
Rocky Shore
Unconsolidated Shore
(Subtotal)
1,151
164
15
1,593
(2,923)
Upper Perennial Unconsolidated Shore 1,658
Unknown Perennial Emergent
Rocky Shore
Unconsolidated Shore
(Subtotal)
71
11
72
(154)
Intermittent Streambed
Unconsolidated Shore
(Subtotal)
38
913
(951)
Total Riverine 6,126
TOTAL MAPPED 1,572,753
60
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table NY-2. Acreage of deepwater habitats for New York based on NWI data in the national database as of September
2009. For this state, the data reflect acreage statistics for 74% of the state where NWI digital data are available (see
Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Subtidal Aquatic Bed
Unconsolidated Bottom
1,501
784,398
Total Marine 785,899
Estuarine Subtidal Aquatic Bed
Unconsolidated Bottom
28,374
818,864
Total Estuarine 847,238
Lacustrine Limnetic Aquatic Bed
Unconsolidated Bottom
152
1,174,429
Total Lacustrine 1,174,581
Riverine Tidal Unconsolidated Bottom 25,425
Lower Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
3
105,090
(105,093)
Upper Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
441
12,203
(13,644)
Unknown Perennial Unconsolidted Bottom 1,065
Total Riverine 145,227
TOTAL MAPPED 2,952,945
61
Wetlands of the Northeast: Results of the National Wetlands Inventory
Pennsylvania
Table PA-1. Acreage of wetlands for Pennsylvania based on NWI data in the national database as of September 2009
(see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Estuarine Intertidal Unconsolidated Shore 55
Total Estuarine 55
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Rock Bottom
Unconsolidated Bottom
Unconsolidated Shore
1,314
59,023 (200 = tidal)
219,101 (220 = tidal)
79,589 (13 = tidal)
2
92
60,452 (5 =tidal)
545 (41 = tidal)
Total Palustrine 420,118 (479 = tidal)
Lacustrine Littoral Aquatic Bed
Emergent
Rock Bottom
Rocky Shore
Unconsolidated Bottom
Unconsolidated Shore
892
266
95
120
6,215
1,221
Total Lacustrine 8,809
Riverine Tidal Emergent
Unconsolidated Shore
(Subtotal)
157
760
(917)
Lower Perennial Emergent
Rocky Shore
Unconsolidated Shore
(Subtotal)
517
31
1,088
(1,636)
Upper Perennial Rocky Shore
Unconsolidated Shore
(Subtotal)
67
434
(501)
Unknown Perennial Emergent
Unconsolidated Shore
(Subtotal)
88
248
(336)
Intermittent Unconsolidated Shore 275
Total Riverine 3,665
TOTAL WETLANDS 432,647
62
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table PA-2. Acreage of deepwater habitats for Pennsylvania based on NWI data in the national database as of
September 2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Estuarine Subtidal Unconsolidated Bottom (UB) 647
Total Estuarine 647
Lacustrine Limnetic Aquatic Bed (UB)
Unconsolidated Bottom (UB)
69
312,140
Total Lacustrine 312,209
Riverine Tidal Unconsolidated Bottom 9,478
Lower Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
92
139,232
(139,324)
Upper Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
46
13,462
(13,508)
Unknown Perennial Unconsolidated Bottom 8,421
Total Riverine 170,731
TOTAL MAPPED 483,587
63
Wetlands of the Northeast: Results of the National Wetlands Inventory
Rhode Island
Table RI-1. Acreage of wetlands for Rhode Island based on NWI data in the national database as of September 2009
(see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Aquatic Bed
Rocky Shore
Unconsolidated Shore
1
215
714
Total Marine 930
Estuarine Intertidal Aquatic Bed
Emergent
Forested
Scrub-Shrub
Rocky Shore
Streambed
Unconsolidated Shore
42
3,678
80
3
62
4
3,419
Total Estuarine 7,288
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Cultivated Cranberry Bog
Unconsolidated Bottom
Unconsolidated Shore
37
3,051 (34 = tidal)
48,665 (94 = tidal)
5,887 (16 = tidal)
107
4,680 (25 = tidal)
27 ( 8 = tidal)
Total Palustrine 62,454 (177 = tidal)
Lacustrine Littoral Emergent
Unconsolidated Shore
4
2
Total Lacustrine 6
TOTAL WETLANDS 70,678
64
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table RI-2. Acreage of deepwater habitats for Rhode Island based on NWI data in the national database as of
September 2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Subtidal Aquatic Bed
Unconsolidated Bottom
1,175
171,455
Total Marine 172,630
Estuarine Subtidal Aquatic Bed
Unconsolidated Bottom
357
88,033
Total Estuarine 88,390
Lacustrine Limnetic Unconsolidated Bottom 19,484
Total Lacustrine 19,484
Riverine Tidal Unconsolidated Bottom 20
Lower Perennial Unconsolidated Bottom 1,059
Total Riverine 1,079
TOTAL MAPPED 281,583
65
Wetlands of the Northeast: Results of the National Wetlands Inventory
Vermont
Table VT-1. Acreage of wetlands for Vermont based on NWI data in the national database as of September 2009. For
this state, the data reflect acreage statistics for 99% of the state where NWI digital data are available (see Figure 5 for
locations and effective date of data based on imagery).
System Subsystem Class Acreage
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Unconsolidated Bottom
Unconsolidated Shore
583
47,222
117,801
59,947
1,114
13,717
80
Total Palustrine 240,464
Lacustrine Littoral Aquatic Bed
Emergent
Unconsolidated Bottom
Unconsolidated Shore
1,188
28
21,129
92
Total Lacustrine 22,437
Riverine Lower Perennial Unconsolidated Shore 242
Upper Perennial Rocky Shore
Unconsolidated Shore
(Subtotal)
2
193
(195)
Intermittent Unconsolidated Shore 45
Total Riverine 482
TOTAL MAPPED 263,383
66
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table VT-2. Acreage of deepwater habitats for Vermont based on NWI data in the national database as of September
2009. For this state, the data reflect acreage statistics for 99% of the state where NWI digital data are available (see
Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Lacustrine Limnetic Aquatic Bed (AB)
AB/Unconsolidated Bottom
Unconsolidated Bottom (UB)
UB/Aquatic Bed
19
2,516
196,871
20
Total Lacustrine 199,426
Riverine Lower Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
6
10,698
(10,704)
Upper Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
171
2,466
(2,637)
Total Riverine 13,341
TOTAL MAPPED 212,767
67
Wetlands of the Northeast: Results of the National Wetlands Inventory
Virginia
Table VA-1. Acreage of wetlands for Virginia based on NWI data in the national database as of September 2009 (see
Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Aquatic Bed
Reef
Unconsolidated Shore
37
55
4,285
Total Marine 4,377
Estuarine Intertidal Aquatic Bed
Emergent
Forested
Scrub-Shrub
Reef
Rocky Shore
Unconsolidated Shore
724
197,335
3,670
3,961
705
5
143,789
Total Estuarine 350,189
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Unconsolidated Bottom
Unconsolidated Shore
644 (23 = tidal)
107,743 (21,839 = tidal)
811,100 (56,238 = tidal)
103,902 (8,123 = tidal)
1,171
82,291 (738 = tidal)
1,164 (10 = tidal)
Total Palustrine 1,108,015 (86,971 = tidal)
Lacustrine Littoral Aquatic Bed
Emergent
Unconsolidated Bottom
Unconsolidated Shore
118
198
3
1,462
2,612
Total Lacustrine 4,393
68
Wetlands of the Northeast: Results of the National Wetlands Inventory
Riverine Tidal Emergent
Unconsolidated Shore
(Subtotal)
500
2,047
(2,547)
Lower Perennial Aquatic Bed
Rocky Sho

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Wetlands of the Northeast:
Results of the National Wetlands Inventory
April 2010
U.S. Fish & Wildlife ServiceWetlands of the Northeast:
Results of the National Wetlands Inventory
April 2010
U.S. Fish & Wildlife Service
Ralph W. Tiner
Regional Wetland Coordinator
Northeast Region
U.S. Fish and Wildlife Service
300 Westgate Center Drive
Hadley, Massachusetts 01035ii
This document should be cited as: Tiner, Ralph W. 2010. Wetlands of the Northeast: Results of the National Wetlands Inventory. U.S. Fish and Wildlife Service, Northeast Region, Hadley, MA. 71 pp.iii
TABLE OF CONTENTS
Wetlands of the Northeast: Results of the National Wetlands Inventory
Executive Summary……………………………………………………………………………………………… v
Acknowledgments……………………………………………………………………………………………… vi
Introduction ……………………………………………………………………………………………………… 1
Study Area …………………………………………………………………………………………………………1
Overview of the Region’s NWI Program …………………���…………………………………………………… 3
Wetlands Inventory ……………………………………………………………………………………………………3
Special Projects ……………………………………………………………………………………………………… 7
Assessing Wetland Changes in the Region ……………………………………………………………………… 7
Expanding NWI Data for Landscape-level Functional Assessment: NWIPlus ……………………………… 7
Potential Wetland Restoration Site Mapping …………………………………………………………………… 9
Assessing Natural Habitat Integrity for Watersheds ………………………………………………………… 9
NWI Mapping for the Northeast ………………………………………………………………………………… 11
Current Status of Mapping ………���…………………………���………………………………………………… 12
Mapping Limitations ………………………………………………………………………………………………… 13
The National Wetlands Database …………………………………………………………………………………… 15
Aggregating Wetland Types for this Report ……………………………………………………………………… 15
Interpretation of Results …………………………………………………………………………………………… 15
Extent of Wetlands and Deepwater Habitats in the Northeast ……………………………………………………17
Summary ………………………………………………………………………………………………………… 22
References ……………………………………………………………………………………………………… 23
Appendix A. List of Contributors to the NWI …………………………………………………………………… 25
Appendix B. Overview of the Service’s Wetland Classification System ………………………………………… 26
Appendix C. List of Regional NWI Publications ………………………………………………………………… 31
Appendix D. Tabular Summaries of NWI Findings for Each State and the District of Columbia ………………… 39
List of Tables
Table 1. Geographic areas where NWIPlus data have been created or are planned for 2010-11 ……………… 8Table 2. Some limitations of NWI data ………………………………………………………………………………14Table 3. Type and coverage of NWI data for each Northeast state and the District of Columbia ………………16Table 4. Wetland acreage for northeastern states and the District of Columbia …………………………………18Table 5. Deepwater habitat acreage for northeastern states and the District of Columbia …………………… 19Table 6. Percent of land area mapped as wetland by the NWI …………………………………………………… 19Table 7. Acreage of major tidal wetland types across the region ………………………………………………… 20Table 8. Acreage of major palustrine wetland types across the region ……………………………………………21
(Note: See Appendix D for acreage summary tables for each state and the District of Columbia)
List of Figures
Figure 1. Ecoregions of the northeastern United States according to Bailey (1994). ……………………………2Figure 2. Example of NWI map produced for Milton, Delaware. …………………………………………………4Figure 3. Custom NWI map for the Milton, Delaware area printed from the “Wetlands Mapper” showing a portion of the area covered in the previous figure. ………………………………………………………………… 5
Figure 4. NWI data for the Milton, Delaware area printed on a topographic base from the U.S. Geological Survey’s National Map. ……………………………………………………………………………………………… 6
Figure 5. Application of natural habitat integrity indices to Midwest states. …………………………………… 10Figure 6. Status of the NWI in the Northeast Region as of September 2009. ……………………………………12Figure 7. Era of imagery for NWI mapping in the Northeast Region as of September 2009. ………………… 12iv
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Executive Summary
Wetlands of the Northeast: Results of the National Wetlands Inventory
The U.S. Fish and Wildlife Service established the National Wetlands Inventory (NWI) in the mid-1970s to map the nation’s wetlands and deepwater habitats. Since then, the NWI has completed at least one phase of mapping for all northeastern states, except New York where roughly three-quarters of the state has been inventoried. For most areas, NWI maps have been converted to digital geospatial data which facilitates generation of acreage summaries of the NWI findings. State reports have been published for several states (Rhode Island, Connecticut, New Jersey, Delaware, and Maryland) and acreage summaries published for most other northeastern states. Since these reports were published, NWI data have been updated for many areas. This report summarizes current NWI data (as of September 2090) for each state from Maine through Virginia and the District of Columbia.
To date, nearly 9 million acres of wetlands have been inventoried by the NWI and are included in its national digital database. Three states had more than one million acres of wetlands: Maine (2.175M acres), New York (1.573M acres with only 74% of the state completed in digital format), and Virginia (1.471M acres). Wetland density (wetland acres/unit area) was highest in states dominated by the coastal plain - Delaware had the highest density of wetland with 21 percent of the state covered by wetland, followed closely by New Jersey with 20 percent. The presence of Chesapeake Bay and its tidal wetlands led to Virginia and Maryland being top-ranked in the acreage of tidal wetlands: Virginia with over 444,000 acres and Maryland with nearly 295,000 acres. New Jersey was the only other state with more than 250,000 acres of tidal wetlands. Estuarine emergent wetlands (salt and brackish marshes) were the predominant tidal wetland type in all coastal states except Maine where estuarine unconsolidated shores (tidal flats) were most common. Maine possessed the most palustrine wetland acreage with about 2 million acres mapped, whereas New York (based on digital wetland data for only 74% of the state) and Virginia both had over one million acres. Other states with more than 400,000 acres of these wetlands were New Jersey, Massachusetts, Maryland, and Pennsylvania. Forested wetlands were the dominant palustrine wetland type in all states, except in West Virginia where unconsolidated bottoms (ponds) were the most common type. Maine had the most acreage of forested and scrub-shrub wetlands mapped with over one million acres and nearly 550,000 acres, respectively.
In addition to creating NWI maps and geospatial data, the Region’s NWI Program has produced a variety of other products including multi-state wetland trends reports, local inventory of wetland change reports, watershed-based wetland characterizations and preliminary functional assessments, and inventories of potential wetland restoration sites. These products plus the digital geospatial data and accompanying status reports have greatly increased our knowledge of the extent, distribution, and diversity of wetlands, their status and trends, wetland functions, and opportunities for their restoration. As such, the NWI has provided vital information to various Service programs, other federal agencies, state agencies, and others that has been used to help protect, conserve, and restore our nation’s wetlands.vi
Wetlands of the Northeast: Results of the National Wetlands Inventory
Acknowledgments
The National Wetlands Inventory (NWI) Program has been actively mapping the nation’s wetlands since the mid-1970s and many people have contributed to the program’s success. For the Northeast Region the actual mapping work was done mostly by a large cadre of photointerpreters and image analysts at the University of Massachusetts (Amherst, MA), the Conservation Management Institute of Virginia Tech University (Blacksburg, VA) and Regional NWI staff with hardcopy maps produced by the NWI Center at St. Petersburg, Florida. Key personnel that should be recognized for the interpretation work - the foundation for the NWI -include former Regional NWI staff - John Anderson, Herbert Bergquist, Anthony Davis, Gabriel DeAlessio, Kelly Drake, David Foulis, Joanne Gookin, Irene Huber, Todd Nuerminger, Sue Schaller, Matt Starr, and William Zinni, former UMass interpreters - chiefly Judy Harding, John LeBlanc, Meredith Borenstein, Kim Santos, Frank Shumway, Jennifer Silva, George Springston, and Janice Stone, and Virginia Tech staff - mainly Matt Fields, Nicole Furman, Kevin McGuckin, and Pamela Swint. Laura Roghair (Virginia Tech) provided analysis of the NWI database that was used to prepare the acreage summaries for this report. The NWI work over the past 35 years was done under the direction of Regional Wetland Coordinator Ralph Tiner with quality control support provided mainly by Assistant Coordinators John Organ, Glenn Smith, and John Swords. Peer review of this report was done by William Kirchner, Jo Ann Mills, John Swords, and Bill Wilen. Gina Jones prepared the report for final publication. Special thanks go to all these individuals plus the agencies and organizations that have contributed in various ways to the success of the NWI Program (Appendix A). 1
Wetlands of the Northeast: Results of the National Wetlands Inventory
Introduction
The Northeast Region of the U.S. Fish and Wildlife Service has been actively mapping wetlands in thirteen states
since the mid-1970s when the National Wetlands Inventory (NWI) Program was established. The NWI Program
was created in 1974 to map the country’s wetlands and provide the Service’s biologists and others with information
on the distribution and diversity of wetlands to aid in wetland conservation efforts. This was the first time that the
federal government produced detailed maps showing the location of the diversity of wetlands that occur across the
nation. The maps serve as invaluable aids for local planning and natural resource conservation.
The purpose of this report is three-fold to: (1) briefly describe the variety of activities performed by the Region’s
NWI Program, (2) increase awareness of the availability of regional NWI reports, and (3) present the findings of the
NWI’s 35 years worth of effort mapping wetlands in the Northeast.
Study Area
The Northeast Region encompasses thirteen states from Maine through Virginia including West Virginia. Major
watersheds in the Region include the drainage basins of the Penobscot, Merrimack, Connecticut, Hudson, Delaware,
Susquehanna, and Potomac Rivers. The Region also contains large coastal embayments including Chesapeake Bay
(the largest estuary in the United States), Delaware Bay, and Long Island Sound plus the Gulf of Maine with its
irregular rocky shoreline and marine-dominated ecosystems. From a physiographic perspective, the region ranges
from the New England-Adirondack Highlands in the north to the Atlantic Coastal Plain, Piedmont, and Appalachian
Highlands in the south, with the major ecosystems varying from boreal forests to broadleaf forests and pine or
mixed pine/hardwood flatwoods (Figure 1). The Region contains a wealth of wetlands including boreal forested
wetlands, bogs, fens, marshes, wet meadows, floodplain wetlands, coastal plain flatwoods, and tidal marshes (see
Tiner 2005 for general descriptions of these types).
2
Wetlands of the Northeast: Results of the National Wetlands Inventory
Figure 1. Ecoregions of the northeastern United States according to Bailey (1994).
212 – Laurentian Mixed Forest Province, M212 – Adirondack-New England Mixed Forest-Coniferous Forest-Alpine
Meadow Province, 221 – Eastern Broadleaf Forest (Oceanic) Province, M221 – Central Appalachian Broadleaf Forest-
Coniferous Forest-Meadow Province,
222 – Eastern Broadleaf Forest (Continental) Province, 231 – Southeastern Mixed Forest Province, and 232 – Outer
Coastal Plain Mixed Forest Province.
3
Wetlands of the Northeast: Results of the National Wetlands Inventory
The Region’s NWI Program is responsible for
conducting the wetland inventory in thirteen
northeastern states from Maine through Virginia. The
main focus of this effort is to produce wetland maps (now
geospatial data) following national standards established
by the Program. Those standards have been recently
adopted as the federal wetland mapping standard by
the Federal Geographic Data Committee (FGDC 2009)
for all federally-funded wetland mapping projects.1
Besides the mapping, the Region’s NWI Program
performs studies to provide the Service and others with
vital information to assist wetland conservation efforts.
This work includes regional and local wetland change
studies, watershed-based wetland characterizations, and
landscape-level assessments of wetland functions.
Wetlands Inventory
The NWI employs conventional photointerpretation
techniques upgraded to utilize modern-day computer
technology to identify, classify, and delineate wetlands
and deepwater habitats. This work is done by image
analysts who interpret spectral signatures from aerial
photographs or digital imagery, separate wetlands from
deepwater habitats from uplands (dryland), delineate
boundaries, and classify wetlands and deepwater
habitats according to the federal government’s official
wetland classification system (Cowardin et al. 1979;
an overview of this system is provided in Appendix
B). Prior to the computer age and desktop mapping,
the interpretations were recorded by pen and ink on
an acetate overlay attached to an aerial photograph.
The annotations were then compiled into map form by
cartographers using zoom transfer scopes at the NWI
Center in St. Petersburg, Florida. Maps were then
digitized manually for computer applications. Today,
the entire operation is done by image analysts on the
computer using geographic information system (GIS)
technology.
At the Program’s inception, the NWI produced maps
at a scale of 1:250,000 map (covering approximately
7,400 square miles). Service field personnel were not
satisfied with this product so eventually large-scale
(1:24,000) maps became the standard product (Figure
2). As computer mapping technology evolved, the
NWI maps were digitized for GIS applications. In the
mid-1990s, the NWI discontinued production of paper
maps in favor of distributing NWI data via online
“mapping tools” where people could make custom
maps for their area of interest. Today, the NWI serves
its data through a tool called the “Wetlands Mapper”
which generates a planimeter map (Figure 3). NWI
data can also be displayed on a topographic map via
the U.S. Geological Survey’s National Map (Figure 4)
or on a current aerial image via a link to Google Earth.
The general public can access and display NWI data
using these tools. More sophisticated GIS users can
connect their applications to real-time data directly
through an online wetland mapping service or download
NWI data for their own applications. Data can be
downloaded by quad or by state. For an overview of the
varied uses of NWI data, see “Status Report for the
National Wetlands Inventory Program: 2009” (Tiner
2009: http://www.fws.gov/wetlands/_documents/gOther/
StatusReportNWIProgram2009.pdf).
Overview of the Region’s NWI Program
1 This standard should be applied to all federal grants involving wetland mapping to insure that such mapping can be added to the NWI’s wetlands
master geospatial database.
4
Wetlands of the Northeast: Results of the National Wetlands Inventory
Figure 2. Example of NWI map produced for Milton, Delaware.
5
Wetlands of the Northeast: Results of the National Wetlands Inventory
Figure 3. Custom NWI map for the Milton, Delaware area printed from the “Wetlands Mapper” showing a portion of the
area covered in the previous figure.
6
Wetlands of the Northeast: Results of the National Wetlands Inventory
Figure 4. NWI data for the Milton, Delaware area printed on a topographic base from the U.S. Geological Survey’s
National Map.
7
Wetlands of the Northeast: Results of the National Wetlands Inventory
Special Projects
While wetland mapping remains the foundation of
the NWI, the Region’s NWI Program has produced
a variety of ancillary products to expand the level of
information provided by the program. These special
projects have substantially added to our knowledge of
Northeast wetlands.
Assessing Wetland Changes in the Region
Knowing how and why wetlands are changing is
vital information for resource managers. The NWI
employs two basic approaches for evaluating wetland
changes: 1) statistically based probabilistic sampling
and 2) inventory of change.2 The former approach
was developed for estimating status and trends of the
nation’s wetlands and involves analyzing changes in
four-square mile plots (Frayer et al. 1983). The NWI
has produced national reports on wetland status and
trends using this approach since the 1980s (e.g., Tiner
1984 and Dahl 2006). This approach provides useful
information for federal agency policy analysts but given
its national focus is not as useful for guiding wetland
conservation efforts at state and local levels. The
Region used this approach for estimating trends in
the five-state Mid-Atlantic region and the Chesapeake
Bay watershed (e.g., Finn and Tiner 1986). The second
approach – inventory of change – was developed by the
Region’s NWI Program for obtaining more detailed
and area-specific information on the nature of local
changes and the underlying causes than generated by
the Service’s national status and trends study. This
approach does not produce estimates of changes, but
instead is an inventory of wetland changes produced
by comparing aerial imagery for the entire geographic
area. Inventories of change have been performed for
certain counties and smaller areas representing just a
couple of 1:24K maps (see Appendix C for a list of these
publications). This type of information is most useful
for analyzing the effectiveness of government efforts
to conserve and protect wetlands in specific geographic
areas. As NWI data are updated in the Northeast,
the Region’s NWI Program plans to produce these
inventories of change, as funding permits, to report on
wetland changes for specific geographic areas as large as
individual states.
Expanding NWI Data for Landscape-level Functional
Assessment: NWIPlus
NWIPlus is an expanded database where other
descriptors are added to the standard NWI database
to improve its utility for preparing more detailed
characterizations of wetland resources and for
predicting wetland functions at the landscape level. In
the 1970s and 1980s, the basic need for wetland data
was inventory-based, that is, knowing where wetlands
were on the landscape and how they differed in terms
of vegetation type and hydrology. With strengthened
wetland regulations since the late 1980s and early 1990s,
another need surfaced - wetland functional assessment.
As techniques were being developed for on-the-ground
assessment of wetland functions, the Region’s NWI
Program sought ways to enhance its inventory so
that landscape-level assessments of wetland functions
could be derived from its database. To accomplish
this, hydrogeomorphic-type descriptors were created
to describe landscape position (i.e., the relationship
between a wetland and a watercourse or waterbody
if present), landform (the shape or physical form of a
wetland), and water flow path (the directional flow of
water). In addition, other descriptors were formulated
to better address the diversity of waterbodies, especially
for ponds, since every wetland trend study has shown
an increase in pond acreage while vegetated wetlands
declined. The type of pond and its landscape context
provide important information for assessing pond
functions. Collectively these descriptors are referred
to as LLWW descriptors (landscape position, landform,
water flow path, and waterbody type; Tiner 2003a).
The NWI has worked with wetland specialists in the
Northeast to develop correlations between wetland
functions and the wetland characteristics recorded
in the NWIPlus database (Tiner 2003b). These
techniques have been used to produce watershed-based
wetland characterizations and preliminary functional
assessments for a number of watersheds in the
Northeast (Table 1).3 A list of available reports is given
in Appendix C.
2 Wetland change analysis is not done by comparing maps since maps produced during different stages of the inventory may not be comparable in
quality. Image-to-image analysis produces a highly accurate and reliable assessment of wetland gains, losses, and changes in type for study areas.
The NWI performs image-to-image analysis for identifying these changes.
3 These techniques have been adopted by several states across the country for their wetland inventories and for utilizing existing wetland data to
predict wetland functions (see article in forthcoming May-June 2010 issue of the National Wetlands Newsletter).
8
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table 1. Geographic areas where NWIPlus data have been created or are planned for 2010-11. A report characterizing
wetlands and their functions was produced or is planned for most areas.
State Geographic Area
Maine Casco Bay watershed
Massachusetts Boston Harbor area, Cape Cod, Nantucket, and Martha’s Vineyard
Rhode Island Entire state
Connecticut Entire state (in progress)
New York Long Island (in progress); New York City water supply watersheds; eleven small
watersheds across the state: Catherine Creek, Cumberland Bay, Hudson River-Snook Kill,
Peconic River, Post Creek to Sing Sing Creek, Salmon River to South Sandy Creek, Sodus
Bay to Wolcott Creek, Sodus Creek, Sucker Brook to Grass River, Upper Tioughnioga
River, and Upper Wappinger Creek
New Jersey Entire state (in progress)
Delaware Nanticoke watershed, entire state (in progress)
Maryland Nanticoke watershed, Coastal Bays watershed
9
Wetlands of the Northeast: Results of the National Wetlands Inventory
Potential Wetland Restoration Site Mapping
Another area of growing interest in wetland
conservation is wetland restoration. In the early
1990s, the Region’s NWI Program worked with the
Massachusetts Executive Office of Environmental
Affair’s Wetlands Restoration and Banking Program
and the University of Massachusetts on special projects
designed to identify potential wetland restoration sites
for some of the state’s watersheds. At that time, the
Massachusetts Wetlands Restoration and Banking
Program applied a watershed-based wetland restoration
approach aimed at targeting wetland restoration in
strategic locations that could help alleviate watershed
problems (e.g., flood damages, degraded water quality,
and fragmented wildlife habitat). The NWI assisted
in developing this approach which ultimately gave the
NWI Program the vision and capability for producing
potential wetland restoration site inventories. Potential
wetland restoration sites include former wetlands that
have been drained or filled but are still in a condition
where restoration is possible (Type 1 restoration sites)
and existing wetlands that have functions impaired by
ditching, excavation, impoundment, or cultivation (Type
2 restoration sites). The former sites are identified
using soil maps and locating hydric soil areas that are
not mapped as NWI wetlands and do not have any
buildings or other structures built upon them. These
restoration site inventories are now often part of
watershed-based wetland inventories and functional
assessments as the data used in these investigations
make it easy to document potential restoration sites.
Through the watershed assessments, it is also possible
to identify sites for possible restoration of streamside
(riparian) vegetation. Depending on project funding and
objectives, the Region’s NWI Program is attempting to
include wetland restoration site inventories as part of its
standard NWI updating procedures.
Assessing Natural Habitat Integrity for Watersheds
Looking beyond wetlands to the entire watershed
is important to assess the “health” of wetlands and
waters since activities in the surrounding landscape
significantly affect water quality and habitat quality of
wetlands. The condition of wetland and stream buffers
is particularly important for wetland and aquatic
wildlife. The widespread availability of land use/cover
geospatial data made it possible to integrate NWI data
with these data to evaluate and report on the condition of
natural habitat surrounding wetlands and waterbodies
and for watersheds as a whole. To accomplish this, the
Region’s NWI Program developed a set of “natural
habitat integrity indices” that can be used for reporting
on the condition of natural habitats for large geographic
areas – a suite of useful metrics for an environmental
report card (Tiner 2004). Thirteen indices were created:
seven addressing habitat extent (i.e., the amount of
natural habitat occurring in the watershed and along
wetlands and waterbodies), four dealing with habitat
disturbances (emphasizing human-induced alterations
to streams, wetlands, and terrestrial habitats), and one
composite index. The eight “natural habitat extent
indices” are natural cover, river corridor integrity,
stream corridor integrity, vegetated wetland buffer
integrity, pond buffer integrity, lake buffer integrity,
wetland extent, and standing waterbody extent. The
four “habitat disturbance indices@ involve dammed
stream flowage, channelized stream flowage, wetland
disturbance, and habitat fragmentation by roads. The
last index - “composite natural habitat integrity index”
– may be calculated in two ways: one is comprised of
the weighted sum of the habitat extent indices minus
the sum of the disturbance indices (weighted composite
natural habitat integrity index), while the alternative is
a simple sum of the extent indices minus the sum of the
disturbance indices (simple summed composite natural
habitat integrity index). These indices were intended to
augment, not supplant, other more rigorous, fine-filter
approaches for describing the ecological condition of
watersheds and for examining relationships between
human impacts and natural resources. The indices can
be used as one metric for an environmental report card
that addresses the changing quality of lands and waters
in specific geographic regions. NWI has applied the
indices to special projects funded by the Service or state
agencies interested in assessing the overall condition
of natural habitat for individual watersheds (e.g., Tiner
and Bergquist 2007). An adjacent Service region (Great
Lakes Region, Region 3) has also applied these indices to
their entire region to produce a map of watershed health
(Figure 5), while the states of Montana and Virginia have
adapted these indices for assessing their watersheds
(e.g., Vance et al. 2009, Ciminelli and Scrivani 2007).
10
Wetlands of the Northeast: Results of the National Wetlands Inventory
Figure 5. Application of natural habitat integrity indices to Midwest states by U.S. Fish and Wildlife Service, Region 3,
Division of Conservation Planning. (Note: This is an early version of the application, contact the Region for the latest
edition.)
11
Wetlands of the Northeast: Results of the National Wetlands Inventory
NWI Mapping for the Northeast
The NWI has complete coverage of wetland data for
all Northeast states except New York. Some areas
have been updated once or twice since the NWI was
initiated in the mid-1970s and state reports have been
published in one form or another for all states except
Massachusetts, Vermont, New York, and Virginia,
although preliminary statistics based on the original
mapping were published for the former two states (see
publications list, Appendix C). Readers should recognize
that an inventory is not a one-time mapping effort,
but instead it is an ongoing process because wetlands
are changing due to both natural forces and human
activities. Also advances in mapping technology make
it possible to improve the accuracy and completeness of
the inventory. New data have been added to the database
for many states, making the previous acreage summaries
reported by NWI obsolete. The most recent findings are
reported in the last major section of this report “Extent
of Wetlands and Deepwater Habitats in the Northeast.”
12
Wetlands of the Northeast: Results of the National Wetlands Inventory
Current Status of Mapping
The status of NWI mapping for the Region as of September 2009 is shown in Figure 6. This report summarizes NWI
acreage data where digital data are available (green areas) as data for other areas are either not available (pink) or
only available in hardcopy maps (tan areas).
The effective date of the NWI across the Region is shown in Figure 7. NWI data are derived not from a single time
period as funding and imagery constraints make this impossible. While most of the data are from the mid-1980s
(green areas), some of the data are from the 1970s (purple areas) and many areas have been recently updated (blue
and red areas). In some areas of the region, development is not occurring at a rapid pace and therefore the mid-
1980s data may still reflect current conditions. The program continues to work in priority areas.
Figure 6. Status of the NWI in the Northeast Region as of
September 2009. Non-digital means only hardcopy maps
are available. The data summaries presented in this
report were derived from the areas shown in green on this
map.
Figure 7. Era of imagery for NWI mapping for the
Northeast Region as of September 2009.
13
Wetlands of the Northeast: Results of the National Wetlands Inventory
Mapping Limitations
The mapping techniques of the NWI have evolved over
time. NWI mapping has improved for a number of
reasons including the availability of higher resolution
imagery, advances in GIS technology, the ability to
integrate NWI data with other geospatial data sources,
and standardized techniques for wetland identification
and delineation. With any mapping effort, there are
limitations due to scale, image quality, and other factors.
Given these considerations, it is impossible to map
every wetland and NWI data are no exception. Some
limitations of NWI mapping are identified in Table 2.
The data presented in this report were derived from
mapping performed using a variety of imagery sources
and during times where our knowledge of wetlands grew
exponentially.
The source imagery affects a number of factors in
wetland mapping: scale (related to smallest wetland
that can be mapped), the emulsion (ability to detect
wetlands), the timing (seasonality affects ability to
detect and classify wetlands), and the date (relates to
the currentness of the inventory, especially in rapidly
developing areas). Since the NWI utilized different
imagery during the course of the inventory, the date
of the imagery used in preparing the NWI can be used
to interpret the mapping detail as follows (Figure 7).
The 1970s imagery (1:80,000 black and white aerial
photography) generally yields a target mapping unit
(tmu) of 3-5 acres. This means that most wetlands
larger than this size range should be mapped, while
smaller wetlands are not consistently shown due to scale
issues. The black and white film also is not as useful for
detecting wetlands as color infrared film, so wetland
mapping is more conservative. The 1980s imagery
(typically 1:58,000 color infrared photography) allows for
a tmu of 1-3 acres in size, whereas the tmu for the 1990s
imagery (1:40,000 color infrared photography) is about 1
acre. The 2000-era imagery is digital imagery of varying
levels of resolution, but is equivalent or better than the
1:40K photography. The tmu for this imagery is ½ acre.
A drawback for some of the 2000-era imagery is that it
is sometimes true color rather than color infrared. True
color imagery is not as reliable for detecting wetlands as
color infrared. However, when interpreting the 2000-era
imagery, existing NWI data are usually being updated,
so the original data derived from color infrared aerial
photography plus the on-screen mapping process allow
the analyst to simultaneously view USDA soil mapping
with the net outcome being an improved wetland map.
While Figure 7 shows the general timeframe of the
imagery, it does not indicate the season in which the
imagery was acquired. Leaf-off imagery is best for
wetland detection. In some areas, such imagery was not
available for the NWI, so leaf-on imagery was used (e.g.,
central and western Pennsylvania). For these areas,
NWI produced a rather conservative inventory as many
forested wetlands were not detectable. When using
NWI data posted online on the Wetlands Mapper (http://
www.fws.gov/wetlands/Data/Mapper.html), readers
should read the accompanying metadata (click on
“Wetland Project Area Metadata”) to learn the specific
date of the imagery used. If summer imagery was the
primary source, the NWI data will be quite conservative.
In any event, when using NWI to determine whether
or not wetland is present on a given parcel of land,
individuals are encouraged to also consult the U.S.
Department of Agriculture’s web soil survey for the
presence of “hydric soils” (http://websoilsurvey.nrcs.
usda.gov/app/HomePage.htm).
14
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table 2. Some limitations of NWI data. (Adapted from Tiner 1999)
1. Target mapping unit (tmu). A tmu is an estimate of the minimum-sized wetland that the NWI is attempting to map and is
largely dependent on photo/image scale. Conspicuous wetlands smaller than the tmu (especially ponds) are often included in the
inventory.
2. Aquatic bed mapping. Since spring (leaf-off) imagery was typically used by the NWI, aquatic beds were not visible since
plants are just beginning to grow at this time and plant parts are well beneath the water’s surface. When observed in the field,
boundaries of these beds were approximated, but typically aquatic beds were included within the waterbody classification –
usually the unconsolidated bottom class.
3. Excessive flooding on imagery. In some cases, extreme high water conditions obscured the life form of the vegetation. While
in many cases, vegetation could be observed underwater, determining whether it was herbaceous or low-growing shrubs was
difficult. Consequently, some shrub wetlands may have been classified as emergent wetlands and vice versa.
4. Use of leaf-on imagery. In central and western Pennsylvania, leaf-on imagery was the only imagery available for the NWI and
resulted in a conservative wetlands inventory as many forested wetlands could not be detected on this imagery. For the rest of
the region, leaf-off imagery was typically available.
5. Temporarily flooded and seasonally saturated forested wetlands. These wetlands occur on higher portions of floodplains or on
nearly level broad plains such as the coastal plain (New Jersey south) or glaciolactustrine plain (e.g., western New York – former
shoreline of Great Lakes). They are among the more difficult wetlands to interpret especially when dominated by evergreen
species. USDA soil survey data have been used to help interpret these areas. NWI data collected prior to 1989 may not show
many of these areas. Availability of digital soils data since then has facilitated identification of these areas based on the presence
of hydric soils.
6. Estuarine wetlands, freshwater tidal wetlands, and tidal waters. Delineation of the break between estuarine and riverine tidal
systems and the oligohaline (slightly brackish) segment of estuaries were based on a combination of limited field observations,
image interpretation, and published reports. The boundaries should be considered approximate. Some tidal swamps may
be classified as nontidal forested wetlands where the upper limit of tidal influence was not mapped to its maximum upstream
penetration.
7. Tidal flats. Since the photos were not synchronized to capture low tide conditions, all tidal flats were not visible on the imagery
used. The boundaries of tidal flats were approximated from coastal and geodetic survey maps and topopgraphic maps when
necessary. Recognize that some of these features, especially sand flats, are dynamic and current locations and boundaries may be
different than those depicted on the maps or in the digital database, especially after major storm events (e.g., hurricanes).
8. Tidal marshes. Identification of high marsh (irregularly flooded) versus low marsh (regularly flooded) is conservative. Most
marshes were identified as high marsh and some low marsh may be included in this type.
9. Water regimes. These hydrologic characteristics were determined based on spectral signatures on the imagery coupled with
findings from limited field investigations. Long-term hydrologic studies would improve the results but were beyond the scope
of the NWI. On the coastal plain and glaciolacustrine plains, the “B” water regime (saturated) was applied to areas that are
seasonally saturated. Note: The earliest NWI mapping applied the temporarily flooded water regime to these wetlands, but it
was later felt that the saturated water regime would better reflect site wetness brought about by seasonal high water tables from
winter to early spring and not by inundation (i.e., ponding in micro-depressions).
10. Farmed wetlands. In the Northeast, the early NWI mapping tended to limit farmed wetlands to cultivated cranberry bogs
due to the ease of their identification. Later, the NWI also mapped depressional wetlands in cultivated fields as farmed wetlands
based on their appearance on aerial imagery. Overall, farmed wetlands are conservatively mapped by the NWI and the actual
acreage of such areas is greater than cited in this report. Determination of farmed wetlands in areas subject to drainage typically
would require a more detailed assessment of their hydrology for accurate identification.
11. Linear wetlands. Long, narrow wetlands that follow drainageways and stream corridors may or may not be mapped
depending on project objectives. Although the hardcopy NWI maps showed these areas, NWI’s online mapping tool - Wetlands
Mapper - does not display such features at this time.
12. Inclusion of uplands. Small upland features may be included within mapped wetland boundaries due to image scale. Field
inspections and analysis of more detailed imagery may be used to identify such features.
15
Wetlands of the Northeast: Results of the National Wetlands Inventory
The National Wetlands Database
The database used to generate the acreage summaries
for this report is maintained by the National Wetlands
Inventory’s National Support and Standards Team
(Madison, WI). Wetland geospatial data for this
report were entered into the national database prior to
September 2009. The data for Northeast wetlands were
produced exclusively by the Region’s NWI Program.4
Data summaries were generated from the polygonal
data in the database (no linear data were analyzed)
by GIS specialists at Virginia Tech’s Conservation
Management Institute (Blacksburg, VA). Data were
summarized for states, counties, and hydrologic units
(HUC-4 and HUC-8 units). Data presented in this
report refer only to the state totals (acreages of wetlands
and deepwater habitats by major type). Data for the
other groupings are available on a limited basis upon
request: contact Ralph Tiner at ralph_tiner@fws.gov. In
the future, these data may be posted online.
Aggregating Wetland Types for This Report
Due to the classification hierarchy that includes
system, subsystem, class, subclass, water regime, and
other modifiers, there are thousands of combinations
possible. To simplify the data for this report, data were
aggregated at the class level. In compiling this regional
summary, mixed classes were assigned to the dominant
class (e.g., PFO1/SS1C was included in the forested
wetland category - PFO, while PSS1/FO1C was placed in
scrub-shrub type - PSS). Marine, Estuarine, Lacustrine
and Palustrine wetlands can be readily identified by
the NWI code (i.e., M2___, E2___, L2___ and P____,
respectively). While some Riverine wetland types can
be clearly identified as wetland by consulting the class
level – unconsolidated shore, rocky shore, or streambed
(intermittent) – or by water regime (not permanently
flooded), open water Riverine wetlands are not easily
recognized since shallow water habitats are not
separated from deep water ones – all are classified either
rock bottom or unconsolidated bottom. Consequently,
all permanently flooded rivers and streams (rock
bottom and unconsolidated bottom) were placed in the
deepwater habitat category for these summaries. The
only exception to this was where the bottom type was
mixed with emergent wetland. The presence of this
vegetation suggests that the area is a shallow water
wetland. This was a rare occurrence. If the open water
area was mixed with aquatic bed vegetation, its acreage
was included in the deepwater habitat summaries since
such vegetation can grow in deep water or as a floating
mat in slow-flowing rivers and streams.
Interpretation of Results
The numbers presented in this report represent the
best available wetland acreage estimates for the areas
completed by the NWI as of September 2009. They
reflect the tabular results of 35-years of mapping by
the program (see Figure 7 for effective inventory date
based on imagery used). For coastal states, the marine
acreage does not reflect the full extent of state waters
as NWI data only go to the limits of the most seaward
U.S. Geological Survey topographic map. Statewide
NWI data are not complete for three states in the
region (Table 3). The numbers presented for New
York represent the findings for about three-quarters
of the state (i.e., digital wetland data). Although NWI
completed wetland mapping for Massachusetts and
Vermont, digital data for a few quads have not been
produced. The findings for these states, however,
represent more than 98 percent of the states. Readers
should refer to Figure 6 to see what parts of these three
states the summary data reflect. Farmed wetlands are
not consistently mapped and in all states, the extent
of farmed wetlands is probably larger than given in
this report. Another important point is that since data
are added to the database periodically, the acreage of
wetlands mapped will change overtime. For the latest
acreage, individuals may want to download NWI data
for a state and generate acreage summaries. For
information on updates since September 2009, contact
contact Ralph Tiner, Regional Wetland Coordinator at
ralph_tiner@fws.gov
4 The national database also includes FGDC-compliant wetland data produced by other organizations, but to date, there are no such data from
northeastern states. In the near future, however, the state of Delaware will be submitting such data for Kent and New Castle Counties.
16
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table 3. Type and coverage of NWI data for each Northeast state and the District of Columbia as of September 2009.
The number represents the % of area covered by the data type.
State
Digital
Data
Hardcopy
Maps Only
No
Data
Connecticut 100.0 -- --
Delaware 100.0 -- --
District of Columbia 100.0 -- --
Maine 100.0 -- --
Maryland 100.0 -- --
Massachusetts 98.0 2.0 --
New Hampshire 100.0 -- --
New Jersey 100.0 -- --
New York 73.9 9.7 16.4
Pennsylvania 100.0 -- --
Rhode Island 100.0 -- --
Vermont 99.2 0.8 --
Virginia 100.0 -- --
West Virginia 100.0 -- --
NWI Data Type
17
Wetlands of the Northeast: Results of the National Wetlands Inventory
Extent of Wetlands and Deepwater Habitats in the
Northeast
The results of the 35-year effort by the NWI are
summarized for the region in a series of tables and
Appendix D. The first two tables (Tables 4 and 5) give
wetland and deepwater totals according to ecological
system for each state and the District of Columbia.
Table 6 shows the percent of the state’s land area that
was occupied by wetland. Tables 7 and 8 address the
dominant types of tidal and palustrine wetlands across
the region. More detailed tabular summaries for each
state and the District of Columbia are given in Appendix
D. These tables include the acreage of specific types
of wetland and deepwater habitat mapped (to the class
level).
Note: Remember that NWI data were not complete for
three states: New York, Massachusetts, and Vermont,
so the results do not represent statewide totals (Table
3; Figure 6). For New York, digital NWI data were
available for 74 percent of the state. For Massachusetts
and Vermont, a few NWI maps were not digitized, so the
results for these states are based on 98 percent and 99
percent coverage, respectively.
Northeastern states with more than one-half million
acres of wetland were Maine (2.175M acres), New York
(1.573M acres for 73.9% of the state mapped by NWI),
Virginia (1.471M acres), New Jersey 0.937M acres),
Maryland (0.701M acres), and Massachusetts (0.536M
acres) (Table 4). Mountainous West Virginia and Rhode
Island, the smallest state in the nation, had the least
wetland acreage.
Five states had more than one million acres of deepwater
habitat mapped (Table 5). New York had the most
acreage due to the presence of Lake Ontario, Long
Island Sound, Peconic Bay, other coastal waters behind
its barrier islands (e.g., Jones Beach Island and Fire
Island), and marine waters offshore. Maine was second-ranked
and had the most marine acreage due to the Gulf
of Maine (e.g., Penobscot and Casco Bays), while Virginia
with the bulk of Chesapeake Bay was third-ranked.
Delaware had the highest density of wetland per land
area with 21 percent of the state represented by wetland
(Table 6). New Jersey was a close second with about 20
percent coverage by wetland. Other states with more
than 10 percent of their land area occupied by wetland
were Maryland, Maine, Massachusetts, and Rhode
Island.
The presence of Chesapeake Bay and its tidal wetlands
led to Virginia and Maryland being top-ranked in the
acreage of tidal wetlands (Table 7). Virginia was first-ranked
with over 444,000 acres mapped, while Maryland
possessed nearly 295,000 acres. New Jersey was third-ranked
with more than 250,000 acres of tidal wetlands,
followed by Maine with almost 168,000 acres. Estuarine
emergent wetlands (salt and brackish marshes) were
the predominant tidal wetland type in all coastal states
except Maine where estuarine unconsolidated shores
(tidal flats) were most common. Maine with its irregular
rocky shoreline had the most acreage of marine
wetlands, comprising about 65 percent of the entire
region’s marine wetlands (Table 4). Rocky shore and
unconsolidated wetlands were the predominant marine
wetland type in Maine, whereas unconsolidated shore
(intertidal beaches and tidal flats) was the most common
type in other states (Table 7).
Palustrine wetlands (freshwater marshes, swamps,
bogs, and ponds) were the most abundant general
wetland type in all states (Table 4). Maine had the
most palustrine wetland acreage with about 2 million
acres mapped, while New York and Virginia both had
over one million acres. When the NWI is completed
for New York that state might end up with the greatest
palustrine wetland acreage. Currently with 74 percent
of the state mapped, 1.5 million acres were reported
and if the acreage in the unmapped portion of the state
has at least the same wetland density as the rest of
the state, New York will have over 2 million acres and
slightly more than was mapped in Maine. Other states
with more than 400,000 acres of these wetlands were,
in order of abundance: New Jersey, Massachusetts,
Maryland, and Pennsylvania. Forested wetlands were
the dominant palustrine wetland type in all states, except
in West Virginia where unconsolidated bottoms (ponds)
were the most common type (Table 8). Maine had the
most acreage of forested and scrub-shrub wetlands
mapped with over one million acres and nearly 550,000
acres, respectively. New York was second-ranked in
both forested and scrub-shrub wetland acreage, in spite
of the fact that the data represent only 74 percent of
the state. Virginia was third-ranked in all categories
of palustrine vegetated wetlands and second-ranked in
pond acreage (unconsolidated bottom). New York had
the most acreage of both palustrine emergent wetlands,
unconsolidated bottom wetlands (ponds), and farmed
wetlands. New Jersey was second-ranked in farmed
wetlands due to the extent of cranberry cultivation,
followed by Massachusetts (another cranberry-producing
state) and Delaware.
18
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table 4. Wetland acreage for northeastern states and the District of Columbia based on NWI data as of September
2009. *Note that NWI digital data for New York covers 74% of the state; see Figure 6 for location of mapped area where
digital data are available.
Marine Estuarine Palustrine Lacustrine Riverine
Total
Wetlands Rank
Connecticut -- 18,788 181,286 1,513 292 201,879 11
Delaware 622 83,082 178,885 54 434 263,077 10
District of Columbia -- -- 237 27 149 413 14
Maine 69,816 83,175 2,000,893 16,495 4,753 2,175,132 1
Maryland 722 248,214 448,214 1,415 1,951 700,516 5
Massachusetts 21,269 61,854 450,114 2,974 168 536,379 6
New Hampshire 886 9,297 280,234 698 1,455 292,570 8
New Jersey 4,224 208,713 719,991 784 3,274 936,986 4
New York 4,983 36,161 1,485,846 39,637 6,126 1,572,753 2
Pennsylvania -- 55 420,118 8,809 3,665 432,647 7
Rhode Island 930 7,288 62,454 6 -- 70,678 12
Vermont -- -- 240,464 22,437 482 263,383 9
Virginia 4,377 350,189 1,108,015 4,393 3,738 1,470,712 3
West Virginia -- -- 54,406 2,550 1,442 58,398 13
Totsl 107,829 1,106,816 7,631,157 101,792 27,929 8,975,523
Acreage Summaries
19
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table 5. Deepwater habitat acreage for northeastern states and the District of Columbia based on NWI data as of
September 2009. *Note that NWI digital data for New York covers 74% of the state; see Figure 6 for mapped area
where digital data are available.
Marine Estuarine Lacustrine Riverine Total Rank
Connecticut -- 349,005 36,341 14,683 400,029 8
Delaware 54,873 271,779 4,176 4,249 335,077 9
District of Columbia -- -- 319 3,944 4,263 14
Maine 1,345,872 78,937 922,796 92,294 2,439,899 2
Maryland 57,415 1,541,510 20,956 38,633 1,658,514 4
Massachusetts 1,048,892 97,459 124,478 21,564 1,292,393 5
New Hampshire 42,842 7,711 166,859 19,677 237,089 12
New Jersey 308,601 508,179 50,594 26,670 894,044 6
New York 785,899 847,238 1,174,581 145,227 2,952,945 1
Pennsylvania -- 647 312,209 170,731 483,587 7
Rhode Island 172,630 88,390 19,484 1,079 281,583 10
Vermont -- -- 199,426 13,341 212,767 11
Virginia 258,673 1,362,007 139,669 146,736 1,907,085 3
West Virginia -- -- 17,089 91,012 108,101 13
Totsl 4,075,697 5,152,862 3,188,977 789,840 13,207,376
Acreage Summaries
Table 6. Percent of land area mapped as wetland by the NWI. Land area comes from U.S. Census 2000 data as reported
by Wikipedia.org. http://simple.wikipedia.org/wiki/List_of_U.S._states_by_area
Land Area
(sq. mi.)
%
Wetland Rank
Connecticut 4,845 6.5 8
Delaware 1,954 21.0 1
District of Columbia 61 1.1 13
Maine 30,862 11.0 4
Maryland 9,774 11.2 3
Massachusetts 7,840 10.9* 5
New Hampshire 8,968 5.1 10
New Jersey 7,417 19.7 2
New York 47,214 7.0* 7
Pennsylvania 44,817 1.5 12
Rhode Island 1,045 10.6 6
Vermont 9,250 4.5* 11
Virginia 39,594 5.8 9
West Virginia 24,078 0.4 14
*NWI digital data does not cover entire state; percent based on NWI acreage versus proportion of state mapped
(MA – 98.0%, NY – 73.9%, and VT – 99.2%).
20
Wetlands of the Northeast: Results of the National Wetlands Inventory
Marine Estuarine Palustrine (tidal) Riverine
US RS Other EM US
Other EM FO SS Other
EM/
US*
Tptal
Area Rank
Connecticut -- -- -- 12,128 6,393 267 1,225 50 349 45 251 20,708 8
Delaware 622 -- -- 77,256 4,880 946 3,229 5,520 1,550 715 434 95,152 5
District of Columbia -- -- -- -- -- -- 7 79 1 2 141 230 12
Maine 26,407 30,141 13,268 22,539 51,620 9,016 2,203 6,144 3,508 405 2,420 167,671 4
Maryland 722 -- -- 205,184 23,670 19,360 3,955 39,960 2,926 250 1,750 294,777 2
Massachusetts 19,488 825 956 44,894 15,501 1,459 1,182 1,808 1,483 352 6 87,954 6
New Hampshire 500 161 225 5,904 3,273 120 110 520 164 60 -- 11,037 9
New Jersey 4,224 12 -- 201,837 5,154 1,722 10,557 18,870 10,584 890 2,731 256,569 3
New York 4,957 18 8 27,684 7,074 1,403 1,558 2,570 499 230 440 46,441 7
Pennsylvania -- -- -- -- 55 -- 200 220 13 46 917 1,451 11
Rhode Island 714 215 1 3,678 3,419 191 34 94 16 33 -- 8,395 10
Virginia 4,285 -- 92 197,335 143,789 9,065 21,839 56,238 8,123 771 2,547 444,084 1
Table 7. Acreage of major tidal wetland types across the region. Note: Freshwater tidal wetlands are represented by Palustrine and Riverine types.
Coding: US – Unconsolidated Shore, RS – Rocky Shore, EM – Emergent, FO – Forested, SS – Scrub-Shrub.
*Acreage is mostly emergent and unconsolidated shore wetland but may include a few acres of minor types (see state tables in Appendix D for details).
21
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table 8. Acreage of major palustrine wetland types across the region. Note: Includes freshwater tidal palustrine wetlands.
Emergent Forested Scrub-Shrub
Unconsolidated
Bottom Other Total Rank
Connecticut 12,613 106,463 27,818 34,135 257 181,286 10
Delaware 11,805 146,412 13,163 3,780 3,725* 178,885 11
District of Columbia 12 183 9 23 10 237 14
Maine 200,952 1,194,848 547,999 55,658 1,436* 2,000,893 1
Maryland 33,958 359,897 35,932 16,649 1,778* 448,214 6
Massachusetts 39,682 293,268 84,562 26,983 5,619* 450,114 5
New Hampshire 39,452 140,451 73,984 26,101 246 280,234 8
New Jersey 67,314 515,951 102,610 27,782 6,334* 719,991 4
New York 219,944 892,019 257,411 92,773 23,699* 1,485,846 2
Pennsylvania 59,023 219,101 79,589 60,452 1,953 420,118 7
Rhode Island 3,051 48,665 5,887 4,680 171* 62,454 12
Vermont 47,222 117,801 59,947 13,717 1,777* 240,464 9
Virginia 107,743 811,100 103,902 82,291 2,979* 1,108,015 3
West Virginia 13,623 12,762 11,198 16,486 337 54,406 13
*Includes farmed wetlands: 3,370 acres in DE, 491 acres in ME (including 307 acres of cultivated cranberry bogs), 662 acres in MD, 4,528 acres in MA
(including 4,473 acres of cranberry bogs), 7,401 acres in NJ (including 4,590 acres of cranberry bogs), 21,731 acres in NY, 107 acres in RI (cranberry
bogs), 1,114 acres in VT, and 1,171 acres in VA.
22
Wetlands of the Northeast: Results of the National Wetlands Inventory
Summary
Since the mid-1970s, the U.S. Fish and Wildlife Service’s NWI Program has completed at least one phase of
mapping for all northeastern states, except New York. Most of the region has NWI data in digital form that allowed
generation of acreage summaries of the NWI findings for each state and the District of Columbia. To date, nearly 9
million acres of wetlands have been mapped and included in the NWI digital database. Three states had more than
one million acres of wetlands recorded: Maine (2.175M acres), New York (1.573M acres with only 74% of the state
completed), and Virginia (1.471M acres). Wetland density (wetland acres/unit area) was highest in states dominated
by the coastal plain - Delaware had the highest density of wetland with 21 percent of the state covered by wetland,
followed closely by New Jersey with 20 percent. Virginia and Maryland, the Chesapeake Bay states, had the most
tidal wetland acreage, followed by New Jersey. Estuarine emergent wetlands (salt and brackish marshes) were the
dominant tidal wetland type across the region, whereas forested wetlands dominated freshwater environments.
In addition to creating NWI maps and geospatial data, the Region’s NWI Program has produced a variety of other
products including multi-state wetland trends analysis reports, inventory of wetland change reports, watershed-based
wetland characterizations and preliminary functional assessments, and inventories of potential wetland
restoration sites. These products plus the digital geospatial data and accompanying status reports have greatly
increased our knowledge of the extent, distribution, and diversity of wetlands, their status and trends, wetland
functions, and opportunities for their restoration. As such, the NWI has provided vital information to various
Service programs, other federal agencies, state agencies, and others that has been used to help protect, conserve,
and restore our nation’s wetlands.
23
Wetlands of the Northeast: Results of the National Wetlands Inventory
References
Bailey, R.G. 1994. Ecoregions of the United States. U.S.D.A. Forest Service, Washington, DC. Map (scale
1:7,500,000). Revised. http://www.fs.fed.us/rm/ecoregions/products/map-ecoregions-united-states/
Ciminelli, J. and J. Scrivani. 2007. Virginia Conservation Lands Needs Assessment: Virginia Watershed Integrity
Model. Virginia Department of Conservation and Recreation-Division of Natural Heritage, Virginia Department
of Forestry, Virginia Commonwealth University-Center for Environmental Studies, and Virginia Department
of Environmental Quality-Coastal Zone Management Program. http://www.dcr.virginia.gov/natural_heritage/
vclnawater.shtml
Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of Wetlands and Deepwater Habitats of
the United States. U.S. Fish and Wildlife Service, Washington, DC. FWS-OBS/79-61. http://library.fws.gov/FWS-OBS/
79_31.pdf
Dahl, T.E. 2006. Status and Trends of Wetlands in the Conterminous United States 1998 to 2004. U.S. Department
of the Interior, Fish and Wildlife Service, Washington, DC. http://www.fws.gov/wetlands/_documents/gSandT/
NationalReports/StatusTrendsWetlandsConterminousUS1998to2004.pdf
FGDC Wetlands Subcommittee. 2009. Wetland Mapping Standard. Federal Geographic Data Committee Document
Number FGDC-STD-015-2009. http://www.fws.gov/wetlands/_documents/gNSDI/FGDCWetlandsMappingStandard.
pdf
Frayer, W.E., T.J. Monahan, D.C. Bowden, and F.A. Graybill. 1983. Status and Trends of Wetlands and Deepwater
Habitats in the Conterminous United States 1950’s to 1970’s. Department of Forest and Wood Sciences, Colorado
State University, Ft. Collins, CO.
Tiner, R.W. (ed.). 2009. Status Report for the National Wetlands Inventory Program: 2009. U.S. Fish and Wildlife
Service, Division of Habitat and Resource Conservation, Branch of Resource and Mapping Support, Washington,
DC. http://www.fws.gov/wetlands/_documents/gOther/StatusReportNWIProgram2009.pdf
Tiner, R.W. 2005. In Search of Swampland: A Wetland Sourcebook and Field Guide. Revised and Expanded 2nd
Edition. Rutgers University Press, New Brunswick, NJ.
Tiner, R.W. 2003a. Dichotomous Keys and Mapping Codes for Wetland Landscape Position, Landform, Water Flow
Path, and Waterbody Type Descriptors. U.S. Fish and Wildlife Service, Northeast Region, Hadley, MA. http://
library.fws.gov/Wetlands/dichotomouskeys0903.pdf
Tiner, R.W. 2003b. Correlating Enhanced National Wetlands Inventory Data With Wetland Functions for Watershed
Assessments: A Rationale for Northeastern U.S. Wetlands. U.S. Fish and Wildlife Service, Northeast Region,
Hadley, MA. http://library.fws.gov/Wetlands/corelate_wetlandsNE.pdf
Tiner, R.W. 2004. Remotely-sensed indicators for monitoring the general condition of “natural habitat” in
watersheds: an application for Delaware’s Nanticoke River watershed. Ecological Indicators 4: 227-243. http://
wetlands.fws.gov/Pubs_Reports/EcologicalIndicatorsTiner.pdf
Tiner, R.W. 1999. Wetland Indicators. A Guide to Wetland Identification, Delineation, Classification, and Mapping.
Lewis Publishers, CRC Press, Boca Raton, FL.
Tiner, R.W. 1984. Wetlands of the United States: Current Status and Recent Trends. U.S. Department of
the Interior, Fish and Wildlife Service, Washington, DC. http://www.fws.gov/wetlands/_documents/gSandT/
NationalReports/WetlandsUSCurrentStatusRecentTrends1984.pdf
Tiner, R.W. and H.C. Bergquist. 2007. The Hackensack River Watershed, New Jersey/New York Wetland
Characterization, Preliminary Assessment of Wetland Functions, and Remotely-sensed Assessment of Natural
Habitat Integrity. U.S. Fish and Wildlife Service, National Wetlands Inventory, Ecological Services, Region 5,
Hadley, MA. http://library.fws.gov/Wetlands/HackensackRiverWatershed07.pdf
24
Wetlands of the Northeast: Results of the National Wetlands Inventory
Tiner, R.W., Jr., and J.T. Finn. 1986. Status and Recent Trends of Wetlands in Five Mid-Atlantic States: Delaware,
Maryland, Pennsylvania, Virginia, and West Virginia. U.S. Fish and Wildlife Service, Region 5, National Wetlands
Inventory Project, Newton Corner, MA and U.S. Environmental Protection Agency, Region III, Philadelphia,
PA. Cooperative publication. http://www.fws.gov/wetlands/_documents/gSandT/StateRegionalReports/
StatusRecentTrendsWetlandsFiveMidAtlanticStates.pdf
Vance, L.K., K. Newlon, J. Clarke, and D.M. Stagliano. 2009. Assessment of Red Rock River Subbasin and Wetlands
of the Centennial Valley. Report to the Bureau of Land Management, Montana/Dakotas State Offices. Montana
Natural Heritage Program, Helena, MT. http://mtnhp.org/Reports/BLM_2009.pdf
25
Wetlands of the Northeast: Results of the National Wetlands Inventory
APPENDIX A. LIST OF PRIMARY CONTRIBUTORS
TO THE NWI FOR THE NORTHEAST
The following agencies have contributed to the Region’s NWI Program by providing funding to support wetland
mapping or other products or have contributed to the NWI Program by performing photointerpretation/image
analysis or distributing NWI maps.
Federal Agencies
Army Corps of Engineers, New England, New York, Philadelphia, and Buffalo Districts
Natural Resource Conservation Service, Maine
Fish and Wildlife Service, Region 5 Refuges Program
Environmental Protection Agency, Regions 1, 2, and 3
Department of Defense
State Agencies
Connecticut Department of Environmental Protection
Delaware Department of Natural Resources and Environmental Control
Maine Geological Survey*
Maine Office of GIS
Maine State Planning Office
Maine Land Use Regulation Commission
Maryland Department of Natural Resources
Maryland Geological Survey*
Massachusetts Executive Office of Environmental Affairs
New Hampshire Office of State Planning*
New Jersey Department of Environmental Protection
New York Department of Environmental Conservation
Pennsylvania Department of Environmental Protection
Rhode Island Department of Environmental Management
Vermont Department of Environmental Conservation*
Virginia Department of Conservation and Recreation
West Virginia Division of Natural Resources
Local Governments
Kent County Conservation District (DE)
New York City Department of Environmental Protection (NY)
Suffolk County (NY)
Tompkins County (NY)
Ulster County (NY)
Universities
Cornell University*
University of Massachusetts*#
Virginia Polytechnic Institute and State University (Virginia Tech) #
*Map distribution centers
#Photointerpretation, image analysis, and data compilation
26
Wetlands of the Northeast: Results of the National Wetlands Inventory
APPENDIX B. OVERVIEW OF THE SERVICE’S
WETLAND CLASSIFICATION SYSTEM
The following section represents a simplified overview
of the Service's wetland classification system.
Consequently, some of the more technical points have
been omitted from this discussion. When actually
classifying a wetland, the reader is advised to refer to
the official classification document (Cowardin et al. 1979;
http://library.fws.gov/FWS-OBS/79_31.pdf) and should
not rely solely on this overview.
Overview of the Service’s Wetland Classification System
The Service's wetland classification system is hierarchial
or vertical in nature proceeding from general to
specific. In this approach, wetlands are first defined at a
rather broad level the SYSTEM. The term SYSTEM
represents "a complex of wetlands and deepwater
habitats that share the influence of similar hydrologic,
geomorphologic, chemical, or biological factors." Five
systems are defined: Marine, Estuarine, Riverine,
Lacustrine, and Palustrine. The Marine System
generally consists of the open ocean and its associated
high energy coastline, while the Estuarine System
encompasses salt and brackish marshes, nonvegetated
tidal shores, and brackish waters of coastal rivers and
embayments. Freshwater wetlands and deepwater
habitats fall into one of the other three systems:
Riverine (rivers and streams), Lacustrine (lakes,
reservoirs and large ponds), or Palustrine (e.g., marshes,
bogs, swamps and small shallow ponds). Thus, at the
most general level, wetlands can be defined as either
Marine, Estuarine, Riverine, Lacustrine or Palustrine.
Each system, with the exception of the Palustrine,
is further subdivided into SUBSYSTEMS. The
Marine and Estuarine Systems both have the same
two subsystems, which are defined by tidal water
levels: (1) Subtidal continuously submerged areas
and (2) Intertidal areas alternately flooded by tides
and exposed to air. Similarly, the Lacustrine System
is separated into two systems based on water depth:
(1) Littoral wetlands extending from the lake shore
to a depth of 6.6 feet (2 m) below low water or to the
extent of nonpersistent emergents (e.g., arrowheads,
pickerelweed, or spatterdock) if they grow beyond
that depth, and (2) Limnetic deepwater habitats lying
beyond the 6.6 feet (2 m) at low water. By contrast, the
Riverine System is further defined by four subsystems
that represent different reaches of a flowing freshwater
or lotic system: (1) Tidal water levels subject to tidal
fluctuations for at least part of the growing season,
(2) Lower Perennial permanent, flowing waters
with a well developed floodplain, (3) Upper Perennial
permanent, flowing water with very little or no floodplain
development, and (4) Intermittent channel containing
nontidal flowing water for only part of the year.
The next level - CLASS - describes the general
appearance of the wetland or deepwater habitat in terms
of the dominant vegetative life form or the nature and
composition of the substrate, where vegetative cover
is less than 30% (Table B-1). Of the 11 classes, five
refer to areas where vegetation covers 30% or more
of the surface: Aquatic Bed, Moss Lichen Wetland,
Emergent Wetland, Scrub Shrub Wetland and Forested
Wetland. The remaining six classes represent areas
generally lacking vegetation, where the composition
of the substrate and degree of flooding distinguish
classes: Rock Bottom, Unconsolidated Bottom, Reef
(sedentary invertebrate colony), Streambed, Rocky
Shore, and Unconsolidated Shore. Permanently flooded
nonvegetated areas are classified as either Rock Bottom
or Unconsolidated Bottom, while exposed areas are
typed as Streambed, Rocky Shore, or Unconsolidated
Shore. Invertebrate reefs are found in both
permanently flooded and exposed areas.
Each class is further divided into SUBCLASSES to
better define the type of substrate in nonvegetated
areas (e.g., bedrock, rubble, cobble gravel, mud, sand,
and organic) or the type of dominant vegetation (e.g.,
persistent or nonpersistent emergents, moss, lichen, or
broad leaved deciduous, needle leaved deciduous, broad-leaved
evergreen, needle leaved evergreen and dead
woody plants). Below the subclass level, DOMINANCE
TYPE can be applied to specify the predominant plant or
animal in the wetland community.
To allow better description of a given wetland or
deepwater habitat in regard to hydrologic, chemical
and soil characteristics and to human impacts, the
classification system contains four types of specific
modifiers: (1) Water Regime, (2) Water Chemistry, (3)
Soil, and (4) Special. These modifiers may be applied to
class and lower levels of the classification hierarchy.
Water regime modifiers describe flooding or soil
saturation conditions and are divided into two main
groups: tidal and nontidal. Tidal water regimes are
used where water level fluctuations are largely driven
by oceanic tides. Tidal regimes can be subdivided into
two general categories, one for salt and brackish water
tidal areas and another for freshwater tidal areas. This
distinction is needed because of the special importance
of seasonal river overflow and ground water inflows in
freshwater tidal areas. By contrast, nontidal modifiers
define conditions where surface water runoff, ground
water discharge, and/or wind effects (i.e., lake seiches)
cause water level changes. Both tidal and nontidal water
regime modifiers are presented and briefly defined in
Table B-2.
Water chemistry modifiers are divided into two
categories which describe the water's salinity or
hydrogen ion concentration (pH): (1) salinity modifiers
and (2) pH modifiers. Like water regimes, salinity
modifiers have been further subdivided into two
27
Wetlands of the Northeast: Results of the National Wetlands Inventory
groups: halinity modifiers for tidal areas and salinity
modifiers for nontidal areas. Estuarine and marine
waters are dominated by sodium chloride, which is
gradually diluted by fresh water as one moves upstream
in coastal rivers. On the other hand, the salinity of
inland waters is dominated by four major cations (i.e.,
calcium, magnesium, sodium, and potassium) and three
major anions (i.e., carbonate, sulfate, and chloride).
Interactions between precipitation, surface runoff,
ground water flow, evaporation, and sometimes plant
evapotranspiration form inland salts which are most
common in arid and semiarid regions of the country.
Table B-3 shows ranges of halinity and salinity modifiers
which are a modification of the Venice System (Remane
and Schlieper 1971). The other set of water chemistry
modifiers are pH modifiers for identifying acid (pH<5.5),
circumneutral (5.5 7.4) and alkaline (pH>7.4) waters.
Some studies have shown a good correlation between
plant distribution and pH levels (Sjors 1950; Jeglum
1971). Moreover, pH can be used to distinguish between
mineral rich (e.g., fens) and mineral poor wetlands (e.g.,
bogs).
The third group of modifiers soil modifiers are
presented because the nature of the soil exerts strong
influences on plant growth and reproduction as well as
on the animals living in it. Two soil modifiers are given:
(1) mineral and (2) organic. In general, if a soil has 20%
or more organic matter by weight in the upper 16 inches,
it is considered an organic soil, whereas if it has less than
this amount, it is a mineral soil. For specific definitions,
please refer to Appendix D of the Service's classification
system (Cowardin et al. 1979) or to Soil Taxonomy (Soil
Survey Staff 1975).
The final set of modifiers special modifiers were
established to describe the activities of people or
beaver affecting wetlands and deepwater habitats.
These modifiers include: excavated, impounded (i.e., to
obstruct outflow of water), diked (i.e., to obstruct inflow
of water), partly drained, farmed, and artificial (i.e.,
materials deposited to create or modify a wetland or
deepwater habitat).
References
Cowardin, L.M., V. Carter, F.C. Golet and E.T. LaRoe. 1979. Classification of Wetlands and Deepwater Habitats of
the United States. U.S. Fish and Wildlife Service, Washington, DC. FWS/OBS 79/31. 103 pp.
Jeglum, J.K. 1971. Plant indicators of pH and water level in peat lands at Candle Lake, Saskatchewan. Can. J. Bot.
49: 1661 1676.
Remane, A. and C. Schlieper. 1971. Biology of Brackish Water. Wiley Interscience Division, John Wiley & Sons,
New York. 372 pp.
Sjors, H. 1950. On the relation between vegetation and electro¬lytes in north Swedish mire waters. Oikos 2: 241
258.
Soil Survey Staff. 1975. Soil Taxonomy. Department of Agriculture, Soil Conservation Service, Washington, DC.
Agriculture Handbook No. 436. 754 pp.
28
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table B-1. Classes and subclasses of wetlands and deepwater habitats (Cowardin et al. 1979).
Class Brief Description Subclasses
Rock Bottom Generally permanently flooded areas with bottom substrates
consisting of at least 75% stones and boulders and less than
30% vegetative cover.
Bedrock; Rubble
Unconsolidated Bottom Generally permanently flooded areas with bottom substrates
consisting of at least 25% particles smaller than stones and
less than 30% vegetative cover.
Cobble-gravel; Sand;
Mud; Organic
Aquatic Bed Generally permanently flooded areas vegetated by plants
growing principally on or below the water surface line.
Algal; Aquatic Moss;
Rooted Vascular;
Floating Vascular
Reef Ridge-like or mound-like structures formed by the
colonization and growth of sedentary invertebrates.
Coral; Mollusk; Worm
Streambed Channel whose bottom is completely dewatered at low
water periods.
Bedrock; Rubble; Cobble-gravel;
Sand; Mud; Organic;
Vegetated (pioneer)
Rocky Shore Wetlands characterized by bedrock, stones or boulders
with areal coverage of 75% or more and with less than 30%
coverage by vegetation.
Bedrock; Rubble
Unconsolidated Shore Wetlands having unconsolidated substrates with less
than 75% coverage by stone, boulders and bedrock and
less than 30% vegetative cover, except by pioneer plants.
Cobble-gravel; Sand;
Mud; Organic;
Vegetated (pioneer)
Moss-Lichen Wetland Wetlands dominated by mosses or lichens where other
plants have less than 30% coverage.
Moss; Lichen
Emergent Wetland Wetlands dominated by erect, rooted, herbaceous
hydrophytes.
Persistent; Nonpersistent
Scrub-Shrub Wetland Wetlands dominated by woody vegetation less than 20
feet (6 m) tall.
Broad-leaved Deciduous;
Needle-leaved Deciduous;
Needle-leaved Evergreen;
Dead
Forested Wetland Wetlands dominated by woody vegetation 20 feet (6 m)
or taller.
Broad-leaved Deciduous;
Needle-leaved Deciduous;
Broad-leaved Evergreen;
Needle-leaved Evergreen;
Dead
29
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table B-2. Water regime modifiers, both tidal and nontidal groups (Cowardin et al. 1979).
Group Type of Water Water Regime Definition
Tidal Saltwater Subtidal Permanently flooded tidal waters
and brackish areas
Irregularly exposed Exposed less often than daily by tides
Regularly flooded Daily tidal flooding and exposure to air
Irregularly flooded Flooded less often than daily and typically
exposed to air
Freshwater Permanently flooded-tidal Permanently flooded by tides and river or
exposed irregularly by tides
Semipermanently flooded-tidal
Flooded for most of the growing season by river
overflow but with tidal fluctuation in water levels
Regularly flooded Daily tidal flooding and exposure to air
Seasonally flooded-tidal Flooded irregularly by tides and seasonally by
river overflow
Temporarily flooded-tidal Flooded irregularly by tides and for brief periods
during growing season by river overflow
Nontidal Inland freshwater and saline
areas
Permanently flooded Flooded throughout the year in all years
Intermittently exposed Flooded year-round except during extreme
droughts
Semipermanently flooded Flooded throughout the growing season in most
years
Seasonally flooded Flooded for extended periods in growing season,
but surface water is usually absent by end of
growing season
Saturated Surface water is seldom present, but substrate is
saturated to the surface for most of the season
Temporarily flooded Flooded for only brief periods during growing
season, with water table usually well below
the soil surface for most of the season
30
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table B-2. Water regime modifiers, both tidal and nontidal groups (Cowardin et al. 1979). continued
Group Type of Water Water Regime Definition
Nontidal Inland freshwater and saline
areas
Intermittently flooded Substrate is usually exposed and only flooded
for variable periods without detectable seasonal
periodicity (not always wetland; may be upland in
some situations)
Artificially flooded Duration and amount of flooding is controlled by
means of pumps or siphons in combination with
dikes or dams
Table B-3. Salinity modifiers for coastal and inland areas (Cowardin et al. 1979).
Coastal
Modifiers5
Inland
Modifiers6
Salinity
(l)
Approximate
Specific
Conductance
(Mhos at 25o C)
Hyperhaline Hypersaline > 40 > 60,000
Euhaline Eusaline 30-40 45,000-60,000
Mixohaline
(Brackish)
Mixosaline7 0.5-30 800-45,000
Polyhaline Polysaline 18-30 30,000-45,000
Mesohaline Mesosaline 5-18 8,000-30,000
Oligohaline Oligosaline 0.5-5 800-8,000
Fresh Fresh < 0.5 < 800
5 Coastal modifiers are employed in the Marine and Estuarine Systems.
6 Inland modifiers are employed in the Riverine, Lacustrine and Palustrine Systems.
7 The term "brackish" should not be used for inland wetlands or deepwater habitats.
31
Wetlands of the Northeast: Results of the National Wetlands Inventory
APPENDIX C. LIST OF REGIONAL NWI
PUBLICATIONS
(Note: Publications are listed by major topic.)
The following is a list of publications produced by the U.S. Fish and Wildlife Service, Northeast Region. Publications
are arranged by general topics. Some of these reports are online publications posted on the NWI website (http://
wetlands.fws.gov), click on “documents search engine” then type in title of the publication in the “key words” block.
Some are online documents at the Service’s Conservation Library and direct links are given. All publications with
numbers in the margin can be obtained free of charge from: U.S, Fish and Wildlife Service, Ecological Services, 300
Westgate Center Drive, Hadley, MA 01035-9589. Your request can be mailed in or emailed to ralph_tiner@fws.gov.
On email, please note "publication order" in the subject block.
WETLAND DEFINITION, CLASSIFICATION, AND BASIC CONCEPTS
101 “Wetlands are Ecotones - Reality or Myth?”
102 “How wet is a wetland?”
103 “The concept of a hydrophyte for wetland identification” (BioScience)
104 “Classification of wetland ecosystems”
195 “A Clarification of the U.S. Fish and Wildlife Service's Wetland Definition”
Dichotomous Keys and Mapping Codes for Wetland Landscape Position, Landform, Water Flow
Path, and Waterbody Type Descriptors by R. Tiner. September 2003.
http://library.fws.gov/Wetlands/dichotomouskeys0903.pdf
167 “Technical Aspects of Wetlands: Wetland Definitions and Classifications in the United States” by
R. Tiner. 1997.
Geographically Isolated Wetlands: A Preliminary Assessment of Their Characteristics and Status
in Selected Areas of the United States2002. U.S. Fish and Wildlife Service, Northeast Region,
Hadley, MA. http://library.fws.gov/Wetlands/isolated.pdf
WETLAND AND RIPARIAN MAPPING
105 “The National Wetlands Inventory - The First Ten Years”
106 “Creating a National Georeferenced Wetland Database for Managing Wetlands in the United
States”
107 “Use of high-altitude aerial photography for inventorying forested wetlands in the United States”
108 NWI Maps Made Easy: A User's Guide to National Wetlands Inventory Maps of the Northeast
Region by G.S. Smith. 1991.
111 Comparison of Four Scales of Color Infrared Photography for Wetland Mapping in Maryland by
R.W. Tiner and G.S. Smith. 1992. U.S. Fish and Wildlife Service, Region 5, Newton Corner, MA.
National Wetlands Inventory Report. R5-92/03. 15 pp. plus tables.
An Investigation and Verification of Draft NWI Maps for Cape May County, New Jersey by U.S.
Fish and Wildlife Service, New Jersey Field Office. 1992. Available from: New Jersey Field Office,
U.S. Fish and Wildlife Service, 927 N. Main Street (Bldg. D-1), Pleasantville, NJ 08232.
158 Map Accuracy of National Wetlands Inventory Maps for Areas Subject to Maine Land Use
Regulation Commission Jurisdiction by C. Nichols. 1994.
32
Wetlands of the Northeast: Results of the National Wetlands Inventory
162 Assessment of Remote Sensing/GIS Technologies to Improve National Wetlands Inventory Maps
by B. Wilen and G. Smith. 1996. Proceedings: Sixth Biennial Forest Service Remote Sensing
Applications Conference, Denver, CO.
164 “Some Uses of National Wetlands Inventory Maps and Digital Map Data in the Northeast”.
166 “NWI Maps: What They Tell Us”.
170 “Adapting the NWI for Preliminary Assessment of Wetland Functions”, R.W. Tiner. 1997. In: The
Future of Wetland Assessment: Applying Science through the Hydrogeomorphic Assessment
Approach and Other Approaches. The Association of State Wetland Managers Institute for Wetland
Science and Public Policy.
171 “NWI Maps--Basic Information on the Nation's Wetlands”, Ralph Tiner. In: BioScience. May 1997.
172 “Piloting a More Descriptive NWI”, Ralph Tiner. In: National Wetlands Newsletter, Vol. 19(5).
September-October 1997.
WETLAND IDENTIFICATION - FIELD GUIDES
Field Guide to Nontidal Wetland Identification by R.W. Tiner, Jr. 1988. Maryland Department of
Natural Resources and U.S. Fish and Wildlife Service. Cooperative publication. 283 pp. + 198 color
plates. Full color reproductions are available for purchase from:. http://www.wetlanded.com
WETLAND DELINEATION - MANUALS/ARTICLES
189 An Overview of Wetland Identification and Delineation Techniques, with Recommendations
for Improvement by Ralph W. Tiner. 2000. Wetland Journal, Volume 12, Number 1, Winter 2000. P.O.
Box P, 201 Boundary Lane, St. Michaels, Maryland 21663, (410) 745-9620
“The Primary Indicators Method - A Practical Approach to Wetland Recognition and Delineation in
the United States” (Wetlands) http://library.fws.gov/Wetlands/TINER_WETLANDS13.pdf
113 “Using Plants as Indicators of Wetland” (Proceedings of The Academy of Natural Sciences of
Philadelphia)
114 “Wetland boundary delineation”
115 “Wetland delineation 1991”
116 “Technical issues regarding wetland delineation”
161 “Practical Considerations for Wetland Identification and Boundary Delineation”
HYDRIC SOILS
Hydric Soils of New England by R.W. Tiner, Jr. and P.L.M. Veneman. Revised edition June 1995. University
of Massachusetts Cooperative Extension, Bulletin C-183R, Amherst, MA. Available from: University of
Massachusetts Extension, Bulletin Center, Cottage A, Thatcher Way, Amherst, MA 01003.
http://www.umassextension.org/Merchant2/merchant.mv
WETLAND PLANT LISTS/HYDROPHYTES
Lists of Potential Hydrophytes for the United States: A Regional Review and Their Use in Wetland
Identification by R.W. Tiner. 2006. WETLANDS 26(2):624-634. Available online at: http://www.fws.gov/
wetlands/ (use documents search engine).
33
Wetlands of the Northeast: Results of the National Wetlands Inventory
WETLAND PLANT - SOIL CORRELATION STUDIES
Soil-Vegetation Correlations in the Connecticut River Floodplain of Western Massachusetts by Peter
Veneman and Ralph Tiner, September 1990, U.S Fish and Wildlife Service, Washington D.C. Biological
Report 90(6). http://library.fws.gov/BiologicalReports/BR_90_6.pdf
STATE WETLAND REPORTS
Wetlands of New Jersey by R.W. Tiner, Jr. 1985. U.S. Fish and Wildlife Service, Region 5, National Wetlands
Inventory Project, Newton Corner, MA. http://library.fws.gov/Wetlands/NJ_wetlands85.pdf
Wetlands of Delaware by R.W. Tiner, Jr. 1985. U.S. Fish and Wildlife Service, Region 5, National Wetlands
Inventory Project, Hadley, MA and Delaware Department of Natural Resources and Environmental
Control, Wetlands Section, Dover, DE. Cooperative publication.
Wetlands of Rhode Island by R.W. Tiner. 1989. U.S. Fish and Wildlife Service, Region 5, National Wetlands
Inventory Project, Newton Corner, MA. http://library.fws.gov/Wetlands/RI_wetlands89.pdf
Wetlands of Connecticut by K. Metzler and R.W. Tiner. 1991. Connecticut Department of Environmental
Protection, Hartford, CT. http://www.fws.gov/wetlands/_documents/gOther/WetlandsConnecticut.pdf
Wetlands of Maryland by R.W. Tiner and D.G. Burke. 1995. U.S. Fish and Wildlife Service, Ecological
Services, Region 5, Hadley, MA and Maryland Department of Natural Resources, Annapolis, MD.
Cooperative publication. http://library.fws.gov/Wetlands/MD_wetlands85.pdf
West Virginia's Wetlands. Uncommon, Valuable Wildlands by R.W. Tiner. 1996. U.S. Fish and Wildlife
Service, Ecological Services, Northeast Region, Hadley, MA. http://www.fws.gov/wetlands/_documents/
gOther/WestVirginiasWetlandsUncommonValuableWildlands.pdf
Current Status of West Virginia's Wetlands by R.W. Tiner. 1996. U.S. Fish and Wildlife Service, Hadley, MA.
http://www.fws.gov/wetlands/_documents/gOther/CurrentStatusWestVirginiasWetlands.pdf
Maine Wetlands and Waters by R.W. Tiner. 2007. U.S. Fish and Wildlife Service, National Wetlands
Inventory Program, Northeast Region, Hadley, MA. Available online at: http://library.fws.gov/Wetlands/
maine07.pdf
New Hampshire Wetlands and Waters by R.W. Tiner. 2007. U.S. Fish and Wildlife Service, National
Wetlands Inventory Program, Northeast Region, Hadley, MA. Available online at: http://library.fws.gov/
Wetlands/NH07.pdf
WETLAND STATUS AND TREND REPORTS (estimates of wetland change)
123 Recent Changes in Estuarine Wetlands of the Conterminous United States by R.W. Tiner. 1991.
Reprinted from "Coastal Wetlands", Coastal Zone '91 Conference-ASCE, Long Beach, CA. 10 pp.
Wetlands of the United States: Current Status and Recent Trends by R.W. Tiner, Jr. 1984. U.S.
Fish and Wildlife Service, National Wetlands Inventory. http://www.fws.gov/wetlands/_documents/
gSandT/NationalReports/WetlandsUSCurrentStatusRecentTrends1984.pdf
124 Status and Recent Trends of Wetlands in Five Mid-Atlantic States: Delaware, Maryland,
Pennsylvania, Virginia, and West Virginia by R.W. Tiner, Jr. and J.T. Finn. 1986.
http://www.fws.gov/wetlands/_documents/gSandT/StateRegionalReports/
StatusRecentTrendsWetlandsFiveMidAtlanticStates.pdf
INVENTORIES OF WETLAND CHANGE REPORTS
125 Current Status and Recent Trends in Wetlands in Central Connecticut by R.W. Tiner, J. Stone, and
J. Gookin. 1989.
34
Wetlands of the Northeast: Results of the National Wetlands Inventory
126 Recent Wetland Trends in Southeastern Massachusetts by R.W. Tiner, Jr. and W. Zinni, Jr. 1988.
127 Pennsylvania's Wetlands: Current Status and Recent Trends by R.W. Tiner. 1990.
128 Current Status and Recent Trends in Wetlands of the Lake Erie and Delaware Estuary Coastal
Zones of Pennsylvania (1986-1989) by G.S. Smith and R.W. Tiner. 1992.
129 Recent Wetland Trends in Anne Arundel County, Maryland (1981-82 to
1988-90) by R.W. Tiner and D.B. Foulis. 1992.
130 Wetland Trends in Prince Georges County, Maryland From 1981 to 1988-89 by R.W. Tiner and D.B.
Foulis. 1992.
131 Wetland Status and Trends for the Pleasant Valley Quadrangle, Dutchess County, New York (1958-
1988) by Ralph W. Tiner and Glenn S. Smith. 1993.
132 “Agricultural impacts on wetlands in the northeastern United States” by Ralph W. Tiner, Jr. 1988.
133 Status and Trends of Wetlands in Cape May County, New Jersey and Vicinity (1977 to 1991) by
G.S. Smith and R.W. Tiner. 1993.
134 Wetland Status and Trends in Selected Areas of Maryland's Piedmont Region (1980-81 to 1988-89)
by R.W. Tiner and D.B. Foulis. 1993.
135 Wetland Status and Trends in Selected Areas of Maryland's Fall Zone (1981-82 to 1988-89) by R.W.
Tiner and D.B. Foulis. 1993.
136 Wetland Trends in Selected Areas of the Western Shore Region of Maryland (1981 to 1988) by R.W.
Tiner and D.B. Foulis. 1993.
137 Wetland Trends for the North East Quadrangle in Maryland (1981 to 1988) by R.W. Tiner and D.B.
Foulis. 1993.
138 Wetland Trends for the Kent Island and Queenstown Quadrangles in Eastern Maryland (1982 to
1989) by R.W. Tiner and D.B. Foulis. 1993.
139 Wetland Trends for the DuBois and Falls Creek Quadrangles in Pennsylvania (1983 to 1988) by
R.W. Tiner and D.B. Foulis. 1993.
140 Wetland Trends in the Williamsport Area of Pennsylvania (1977 to 1988/90) by R.W. Tiner and D.B.
Foulis. 1993.
141 Wetland Trends for the Hazelton Quadrangle in Pennsylvania (1981 to 1987) by R.W. Tiner and
D.B. Foulis. 1993.
142 Wetland Trends in Selected Areas of the Greater Harrisburg Region of Pennsylvania (1983-84 to
1987-88) by R.W. Tiner and D.B. Foulis. 1993.
143 Wetland Trends for Selected Areas of the Northeast Glaciated Region of Pennsylvania (1981-82 to
1987-88) by R.W. Tiner, D.B. Foulis, and T.W. Nuerminger. 1994.
144 Wetland Trends for Selected Areas of Dorchester County, Maryland and Vicinity (1981-82 to 1988-
89) by R.W. Tiner and D.B. Foulis. 1994.
144a Wetland Trends in Dorchester County, Maryland (1981-82 to 1988-89) by D.B. Foulis, T.W.
Nuerminger, and R.W. Tiner. 1995.
145 Wetland Trends for Selected Areas of the Lower Eastern Shore of the Delmarva Peninsula (1982 to
1988-89) by R.W. Tiner and D.B. Foulis. 1994.
146 Wetland Trends in Selected Areas of the Norfolk/Hampton Region of Virginia (1982 to 1989-90) by
R.W. Tiner and D.B. Foulis. 1994.
35
Wetlands of the Northeast: Results of the National Wetlands Inventory
147 Wetland Trends for Selected Areas in Northern Virginia (1980-81 to 1988/91) by R.W. Tiner and
D.B. Foulis. 1994.
148 Wetland Trends for Selected Areas of the Chickahominy River Watershed of Virginia (1982/84 to
1989-90) by R.W. Tiner and D.B. Foulis. 1994.
Recent Wetland Status and Trends in the Chesapeake Watershed (1982 to 1989): Technical Report
by R.W. Tiner, I. Kenenski, T. Nuerminger, D.B. Foulis, J. Eaton, G.S. Smith, and W.E.
Frayer. 1994. Chesapeake Bay Program, Annapolis, MD. http://www.fws.gov/wetlands/_documents/
gSandT/StateRegionalReports/RecentWetlandStatusTrendsChesapeakeWatershed1982to1989.pdf
149 Recent Wetland Status and Trends in the Chesapeake Watershed (1982 to 1989): Executive
Summary Report by R.W. Tiner. 1994.
150 Wetland Trends for Selected Areas of the Casco Bay Estuary of the Gulf of Maine (1974-77 to 1984-
87) by D.B. Foulis and R.W. Tiner. 1994.
151 Wetland Trends for Selected Areas of the Cobscook Bay/St. Croix River Estuary of the Gulf of
Maine (1975/77 to 1983-85) by D.B. Foulis and R.W. Tiner. 1994.
152 Wetland Trends for Selected Areas of the Coast of Massachusetts, from Plum Island to Scituate
(1977 to 1985-86) by D.B. Foulis and R.W. Tiner. 1994.
153 Wetland Trends for Selected Areas of the Gulf of Maine, from York, Maine to Rowley,
Massachusetts (1977 to 1985-86) by D.B. Foulis, J.A. Eaton, and R.W. Tiner. 1994.
154 Wetland Status and Trends in Charles County, Maryland (1981 to 1988-89) by D.B. Foulis and R.W.
Tiner. 1994.
155 Wetland Status and Trends in St. Marys County, Maryland (1981-82 to 1988-89) by D.B. Foulis
and R.W. Tiner. 1994.
156 Wetland Status and Trends in Calvert County, Maryland (1981-82 to 1988-89) by D.B. Foulis and
R.W. Tiner. 1994.
168 New York Tidal Wetland Trends: Pilot Study in Shinnecock Bay Estuary and Recommendations
for Statewide Analysis by R.W. Tiner. 1987.
173 Current Status of West Virginia's Wetlands: Results of the National Wetlands Inventory by R.W.
Tiner. 1996.
Chesapeake Bay Wetlands: The Vital Link Between the Watershed and the Bay. 14 pp. booklet.
Available from: U.S. Fish and Wildlife Service, Chesapeake Bay Field Office, 177 Admiral Cochrane
Drive, Annapolis, MD 21401; (410) 573-4583.
177 Wetland Status and Recent Trends for the Neponset Watershed, Massachusetts (1977-1991) by
R.W. Tiner, D.B. Foulis, C. Nichols, S. Schaller, D. Petersen, K. Andersen, and John Swords. 1998.
Delaware’s Wetlands: Status and Recent Trends by R.W. Tiner. June 2001. http://www.fws.gov/
wetlands/_documents/gSandT/StateRegionalReports/DelawaresWetlandsStatusRecentTrends.pdf
Wetland Status and Trends for the Hackensack Meadowlands: An Assessment Report from the
National Wetlands Inventory Program by R.W. Tiner, J.Q. Swords, and B.J. McClain. 2002.
http://library.fws.gov/wetlands/hackensack.pdf.
Coastal Wetland Trends in the Narragansett Bay Estuary During the 20th Century by R.W. Tiner,
I.J. Huber, T. Nuerminger, and A.L. Mandeville. 2004. http://library.fws.gov/Wetlands/
narragansett04.pdf
Recent Wetland Trends in Southeastern Virginia: 1994-2000. by R.W. Tiner, J.Q. Swords, and
H.C. Bergquist. 2005. http://library.fws.gov/Wetlands/sevirginia05.pdf
36
Wetlands of the Northeast: Results of the National Wetlands Inventory
100 Years of Estuarine Marsh Trends (1893 to 1995): Boston Harbor, Cape Cod, Nantucket,
Martha’s Vineyard, and the Elizabeth Islands by B.K. Carlisle, R.W. Tiner, M. Carullo, I. J. Huber,
T. Nuerminger, C. Polzen, and M. Shaffer. 2006. http://www.mass.gov/czm/estuarine_marsh_
trend1.htm
Mid-Atlantic Wetlands: A Disappearing Natural Treasure by R.W. Tiner. 1987.
http://library.fws.gov/Wetlands/midatlantic.pdf
Salt Marsh Trends in Selected Estuaries in Southwestern Connecticut by R.W. Tiner and others.
2006. http://library.fws.gov/wetlands/saltmarsh_ct06.pdf
INVENTORY REPORTS/ARTICLES
182 Wetland Trends in the Croton Watershed, New York (1968-1994) by R. Tiner, J. Swords, and S.
Schaller. 1999.
183 Wetland Trends in Delaware: 1981/2 to 1992 by R. Tiner, J. Swords, and S. Schaller. 1999.
192 The Peconic Watershed: Recent Trends in Wetlands and their Buffers. R.W. Tiner and others. 2000.
201 Geographically Isolated Wetlands of the United States by R.W. Tiner, U. S. Fish and Wildlife
Service. Also in Wetlands, Vol 23, No.3, Sept. 2003, pp 494-516, The Society of Wetland Scientists
202 Estimated Extent of Geographically Isolated Wetlands in Selected Areas of the United States
by Ralph Tiner, U.S. Fish and Wildlife Service. In Wetlands, Vol 23, No.3, Sept. 2003, pp 636-652,
The Society of Wetland Scientists
OTHER REGIONAL WETLAND INVENTORY REPORTS/ARTICLES
117 Preliminary NWI Wetland Acreage Reports for Massachusetts (1992) and Vermont (1987) by R. W.
Tiner, U.S. Fish and Wildlife Service, NWI Project, Newton Corner, MA
118 Wetlands Inventory of the FAA Technical Center, Atlantic City International Airport, New Jersey
by Ralph W. Tiner and Glenn S. Smith. 1993.
119 "Vascular plant communities in wetlands of Pennsylvania"
120 "Current status and recent trends in Pennsylvania's wetlands"
121 "Wetlands of the Delaware River Basin"
The Wetlands of Acadia National Park and Vicinity. A joint publication of the Department of
Wildlife Ecology, University of Maine; the Maine Agricultural and Forest Experiment Station; the
National Park Service; and the U.S. Fish and Wildlife Service. 1994. Miscellaneous Publication
721. Available from: Publications Office, Room 1, Maine Agricultural and Forest Expt. Station, 5782
Winslow Hall, University of Maine, Orono, ME 04469-5782; (207) 581-1110.
174 Wetlands in the Watersheds of the New York Water Supply System. R.W. Tiner. 1997. 17 pp. color
booklet. Limited copies through U.S. Fish and Wildlife Service. Available from: Laurie Machung,
New York City Department of Environmental Protection, Watershed Office of Public Affairs, 71
Smith Avenue, Kingston, NY 12401; (845) 340-7524.
Mid Atlantic Wetlands - A Disappearing Natural Treasure. R.W. Tiner, Jr., June 1987.
http://library.fws.gov/Wetlands/midatlantic.pdf
Wetlands of Saratoga County, New York. R. Tiner. 2000. 20 pp. color booklet. A Cooperative
National Wetlands Inventory Report. http://www.fws.gov/wetlands/_documents/gOther/
WetlandsSaratogaCounty.pdf
37
Wetlands of the Northeast: Results of the National Wetlands Inventory
Wetlands of Staten Island, New York. R. Tiner. 2000. 20 pp. color booklet. A Cooperative National
Wetlands Inventory Report. http://www.fws.gov/wetlands/_documents/gOther/
WetlandsStatenIsland.pdf
180 Wetlands and Deepwater Habitats at Saratoga County, New York; The Results of the National
Wetlands Inventory, by R.W. Tiner, I.K. Huber, D.B. Foulis, T. Nuerminger, G.S. Smith and M. J.
Starr. 2000.
Geographically Isolated Wetlands: A Preliminary Assessment of Their Characteristics and Status
in Selected Areas of the United States 2002. U.S. Fish and Wildlife Service, Northeast Region,
Hadley, MA. http://www.fws.gov/wetlands/_documents/gOther/GeographicallyIsolatedWetlandsFS.
pdf
Wetlands of the Boston Harbor Islands National Recreation Area by R. W. Tiner, J. Q. Swords,
and H.C. Bergquist. 2003. U.S. Fish and Wildlife Service, Northeast Region, Hadley, MA.
http://library.fws.gov/wetlands/boston_harbor03.pdf.
SUBMERGED AQUATIC VEGETATION SURVEYS
Eelgrass Survey for Eastern Long Island Sound, Connecticut and New York. R. Tiner, H. Bergquist, T.
Halavick, and A. MacLachlan. 2003.
2006 Eelgrass Survey for Eastern Long Island Sound, Connecticut and New York. R. Tiner, H.
Bergquist, T. Halavick, and A. MacLachlan. 2007. http://library.fws.gov/Wetlands/eelgrass_report_2006.pdf
An Inventory of Submerged Aquatic Vegetation and Hardened Shorelines of the Peconic Estuary, New York
by R.W. Tiner and others. 2003. http://library.fws.gov/Wetlands/peconic03.pdf
WETLAND RESTORATION AND CREATION (INCLUDING STREAM BUFFERS)
175 Wetland Restoration and Creation by R.W. Tiner. 1995.
Managing Common Reed (Phragmites australis) in Massachusetts: An Introduction to the Species
and Control Techniques by R. Tiner. 1998. http//www.massaudubon.org/Kids/Lively_Lessons/
Saltmarsh/restoration.html
187 Restoring Wetland and Streamside/Riparian Buffers by R.W. Tiner. 2003.
WETLAND MONITORING
179 Wetland Monitoring Guidelines: Operational Draft. U.S. Fish and Wildlife Service, Region 5,
Hadley, MA.
WETLAND EVALUATION/ASSESSMENT
Correlating Enhanced National Wetlands Inventory Data with Wetland Functions for Watershed
Assessments: A Rationale for Northeastern U.S. Wetlands by R. Tiner, October 2003. http://wetlands.fws.
gov/Pubs_Reports/HGMReportOctober2003.pdf
WATERSHED-BASED WETLAND STUDIES: CHARACTERIZATION AND PRELIMINARY FUNCTIONAL
ASSESSMENT, WETLAND RESTORATION, AND OVERALL ECOLOGICAL INTEGRITY
Historical Analysis of Wetlands and Their Functions for the Nanticoke River Watershed: A Comparison
Between Pre-settlement and 1998 Conditions. R. W. Tiner and H.C. Bergquist. 2003. http://library.fws.gov/
wetlands/Nanticoke04.pdf
38
Wetlands of the Northeast: Results of the National Wetlands Inventory
An Inventory of Coastal Wetlands, Potential Restoration Sites, Wetland Buffers, and Hardened Shorelines
for the Narragansett Bay Estuary: An Assessment Report from the National Wetlands Inventory Program.
R.W. Tiner and others. 2003. http://library.fws.gov/wetlands/RIcoast03.pdf
The Parker River Watershed: An Assessment of Recent Trends in Salt Marshes, Their Buffers, and River-
Stream Buffer Zones (1985-1999). 2002. http://library.fws.gov/wetlands/parkerriver02.pdf
Wetland Characterization and Preliminary Assessment of Wetland Functions for the Delaware and
Catskill Watersheds of the New York City Water Supply System. R.W. Tiner and J. Stewart. 2004.
Wetland Characterization and Preliminary Assessment of Wetland Functions for the Croton Watershed of
the New York City Water Supply System. R.W.Tiner, C.W. Polzen, and B. J. McClain. 2004.
Watershed-based Wetland Characterization for Maryland's Nanticoke River and Coastal Bays Watersheds:
A Preliminary Assessment Report. R.W. Tiner and others. 2000. http://www.fws.gov/wetlands/_documents/
gOther/WatershedbasedWetlandCharacterizationMarylandsNanticokeRiverWatershed.pdf
Watershed-based Wetland Characterizations for Delaware's Nanticoke River Watershed: A Preliminary
Assessment Report. R.W. Tiner and others. 2001. http://library.fws.gov/wetlands/DEnanticoke01.pdf
197 Enhancing Wetlands Inventory Data for Watershed-based Wetland Characterizations and
Preliminary Assessments of Wetland Functions. R.W. Tiner. 2002.
198 Remotely-sensed Natural Habitat Integrity Indices for Assessing the General Ecological
Condition of Watersheds. R.W. Tiner. 2002
Watershed-based Wetland Planning and Evaluation. A Collection of Papers from the Wetland
Millennium Event (August 6-12, 2000; Quebec City, Quebec, Canada). http://www.aswm.org/
propub/pubs/pdf/tiner_2002_wshed.pdf
180 Wetland Characterization Study and Preliminary Assessment of Wetland Functions for the Casco
Bay Watershed, Southern Maine. by R.W. Tiner and others. 1999. U.S. Fish and Wildlife Service,
Region 5, Hadley, MA.
185 Wetland Characterization and Preliminary Assessment of Wetland Functions for the Boyds
Corner and West Branch Sub-basins of the Croton Watershed, New York by R. Tiner, S. Schaller,
and M. Starr. 1999.
193 Wetlands and Potential Wetland Restoration Sites for the Mill Rivers and Manhan River
Watershed. R.W. Tiner and others. 2000
194 Wetlands and Potential Wetland Restoration Sites for the Shawsheen Watershed. R.W. Tiner and
others. 2000. (Cooperative USFWS and University of Massachusetts report)
Correlating Enhanced National Wetlands Inventory Data with Wetland Functions for Watershed
Assessments: A Rationale for Northeastern U.S. Wetlands by R. Tiner, October 2003. http://library.
fws.gov/Wetlands/corelate_wetlandsNE.pdf
Remotely-sensed indicators for monitoring the general condition of "natural habitat" in
watersheds: an application for Delaware's Nanticoke River watershed by R. Tiner. Published in
Ecological Indicators 4 (2004): 227-243. Contact ralph_tiner@fws.gov for copy.
205 Wetlands and Potential Wetland Restoration Sites for the Upper Ipswich Watershed.
WETLAND PROTECTION
201 Geographically Isolated Wetlands of the United States by R.W. Tiner, U. S. Fish and Wildlife
Service. Wetlands, Vol 23, No.3, Sept. 2003, pp. 494-516, The Society of Wetland Scientists.
39
Wetlands of the Northeast: Results of the National Wetlands Inventory
APPENDIX D. TABULUAR SUMMARIES OF NWI
FINDINGS FOR EACH STATE AND THE DISTRICT OF
COLUMBIA
(Note: Data are presented for each area alphabetically. Two tables are given: one for wetlands and the other for
deepwater habitat totals.)
Connecticut
Table CT-1. Acreage of wetlands for Connecticut based on NWI data in the national database as of September 2009
(see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Estuarine Intertidal Aquatic Bed
Emergent
Scrub-Shrub
Rocky Shore
Unconsolidated Shore
94
12,128
57
116
6,393
Total Estuarine 18,788
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Unconsolidated Bottom
Unconsolidated Shore
238
12,613 (1,225 = tidal)
106,463 (50 = tidal)
27,818 (349 = tidal)
1
34,135 (45 = tidal)
18
Total Palustrine 181,286 (1,669 = tidal)
Lacustrine Littoral Aquatic Bed
Emergent
Unconsolidated Bottom
Unconsolidated Shore
565
185
741
22
Total Lacustrine 1,513
Riverine Tidal Emergent
Unconsolidated Shore
(Subtotal)
167
84
(251)
Lower Perennial Rocky Shore
Unconsolidated Shore
(Subtotal)
16
24
(40)
Upper Perennial Unconsolidated Shore 1
Total Riverine 292
TOTAL MAPPED 201,879
40
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table CT-2. Acreage of deepwater habitats for Connecticut based on NWI data in the national database as of
September 2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Estuarine Subtidal Unconsolidated Bottom (UB) 349, 005
Total Estuarine 349,005
Lacustrine Limnetic Aquatic Bed (UB)
Unconsolidated Bottom
87
36,254
Total Lacustrine 36,341
Riverine Tidal Unconsolidated Bottom 7,356
Lower Perennial Rocky Shore
Unconsolidated Bottom
(Subtotal)
86
4,819
(4,905)
Upper Perennial Unconsolidated Bottom 2,422
Total Riverine 14,683
TOTAL MAPPED 400,029
41
Wetlands of the Northeast: Results of the National Wetlands Inventory
Delaware
Table DE-1. Acreage of wetlands for Delaware based on NWI data in the national database as of September 2009 (see
Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Unconsolidated Shore 622
Total Marine 622
Estuarine Intertidal Emergent
Forested
Scrub-Shrub
Unconsolidated Shore
77,256
11
935
4,880
Total Estuarine 83,082
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Unconsolidated Bottom
Unconsolidated Shore
14 (7 = tidal)
11,805 (3,229 = tidal)
146,412 (5,520 = tidal)
13,163 (1,550 = tidal)
3,370
3,780 (562 = tidal)
341 (146 = tidal)
Total Palustrine 178,885 (11,014 = tidal)
Lacustrine Littoral Emergent
Unconsolidated Bottom
12
42
Total Lacustrine 54
Riverine Tidal Emergent
Unconsolidated Shore
239
195
Total Riverine 434
TOTAL MAPPED 263,077
42
Wetlands of the Northeast: Results of the National Wetlands Inventory
System Subsystem Class Acreage
Marine Subtidal Unconsolidated Bottom 54,873
Total Marine 54,873
Estuarine Subtidal Unconsolidated Bottom 271,779
Total Estuarine 271,779
Lacustrine Limnetic Unconsolidated Bottom 4,176
Total Lacustrine 4,176
Riverine Tidal Unconsolidated Bottom 3,762
Lower Perennial Unconsolidated Bottom 487
Total Riverine 4,249
TOTAL MAPPED 335,077
Table DE-2. Acreage of deepwater habitats for Delaware based on NWI data in the national database as of September
2009 (see Figure 5 for locations and effective date of data based on imagery).
43
Wetlands of the Northeast: Results of the National Wetlands Inventory
District of Columbia
Table DC-1. Acreage of wetlands and deepwater habitats for District of Columbia, DC based on NWI data in the
national database as of September 2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Unconsolidated Bottom
Unconsolidated Shore
9
12 (7 = tidal)
183 (79 = tidal)
9 (1 = tidal)
23 (2 = tidal)
1
Total Palustrine 237 (89 = tidal)
Lacustrine Littoral Emergent
Unconsolidated Shore
26
1
Total Lacustrine 27
Riverine Tidal Emergent
Unconsolidated Shore
(Subtotal)
30
111
(141)
Lower Perennial Unconsolidated Shore 4
Upper Perennial Unconsolidated Shore 4
Total Riverine 149
TOTAL MAPPED 413
44
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table DC-2. Acreage of deepwater habitats for the District of Columbia based on NWI data in the national database as
of September 2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Lacustrine Limnetic Unconsolidated Bottom 319
Total Lacustrine 319
Riverine Tidal Unconsolidated Bottom 3,928
Upper Perennial Unconsolidated Bottom 16
Total Riverine 3.944
TOTAL MAPPED 4,263
45
Wetlands of the Northeast: Results of the National Wetlands Inventory
Maine
Table ME-1. Acreage of wetlands for Maine based on NWI data in the national database as of September 2009 (see
Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Aquatic Bed
Rocky Shore
Unconsolidated Shore
13,268
30,141
26,407
Total Marine 69,816
Estuarine Intertidal Aquatic Bed
Emergent
Scrub-Shrub
Rocky Shore
Streambed
Unconsolidated Shore
6,853
22,539
99
2,058
6
51,620
Total Estuarine 83,175
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Cultivated Cranberry Bog
Unconsolidated Bottom
Unconsolidated Shore
139
200,952 (2,203 = tidal)
1,194,848 (6,144 = tidal)
547,999 (3,508 = tidal)
184
307
55,658 (403 = tidal)
806 (2 = tidal)
Total Palustrine 2,000,893 (12,260 = tidal)
Lacustrine Littoral Aquatic Bed
Emergent
Rocky Shore
Unconsolidated Bottom
Unconsolidated Shore
115
260
7,950
458
7,712
Total Lacustrine 16,495
46
Wetlands of the Northeast: Results of the National Wetlands Inventory
Riverine Tidal Aquatic Bed
Emergent
Rocky Shore
Unconsolidated Shore
(Subtotal)
11
86
3
2,320
(2,420)
Lower Perennial Emergent
Rocky Shore
Unconsolidated Shore
(Subtotal)
13
38
1,185
(1,236)
Upper Perennial Rocky Shore
Unconsolidated Shore
(Subtotal)
13
1,083
(1,096)
Total Riverine 4,753
TOTAL MAPPED 2,175,132
47
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table ME-2. Acreage of deepwater habitats for Maine based on NWI data in the national database as of September
2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Subtidal Aquatic Bed
Unconsolidated Bottom
2,557
1,343,315
Total Marine 1,345,872
Estuarine Subtidal Aquatic Bed
Rock Bottom
Unconsolidated Bottom
12
13
78,922
Total Estuarine 78,937
Lacustrine Limnetic Aquatic Bed
Unconsolidated Bottom
14
922,782
Total Lacustrine 922,796
Riverine Tidal Rock Bottom
Unconsolidated Bottom
(Subtotal)
3
6,554
(6,557)
Lower Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
59
69,659
(69,718)
Upper Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
122
155,897
(16,019)
Total Riverine 92,294
TOTAL MAPPED 2,439,899
48
Wetlands of the Northeast: Results of the National Wetlands Inventory
Maryland
Table MD-1. Acreage of wetlands for Maryland based on NWI data in the national database as of September 2009 (see
Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Unconsolidated Shore 722
Total Marine 722
Estuarine Intertidal Emergent
Forested
Scrub-Shrub
Rocky Shore
Unconsolidated Shore
205,184
16,870
2,488
2
23,670
Total Estuarine 248,214
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Rock Bottom
Unconsolidated Bottom
Unconsolidated Shore
426
33,958 (3,955 = tidal)
359,897 (36,960 = tidal)
35,932 (2,926 = tidal)
662
140
16,649 (248 = tidal)
550 (2 = tidal)
Total Palustrine 448,214 (44,091 = tidal)
Lacustrine Littoral Aquatic Bed
Emergent
Rocky Shore
Unconsolidated Bottom
Unconsolidated Shore
6
535
8
139
727
Total Lacustrine 1,415
49
Wetlands of the Northeast: Results of the National Wetlands Inventory
Riverine Tidal Emergent
Unconsolidated Shore
(Subtotal)
1,574
176
(1,750)
Lower Perennial Emergent
Unconsolidated Shore
(Subtotal)
6
126
(132)
Upper Perennial Rocky Shore
Unconsolidated Shore
(Subtotal)
6
48
(54)
Unknown Perennial Rocky Shore
Unconsolidated Shore
(Subtotal)
4
11
(15)
Total Riverine 1,951
TOTAL MAPPED 700,516
50
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table MD-2. Acreage of deepwater habitats for Maryland based on NWI data in the national database as of September
2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Subtidal Unconsolidated Bottom 57,415
Total Marine 57,415
Estuarine Subtidal Aquatic Bed
Unconsolidated Bottom
2
1,541,508
Total Estuarine 1,541,510
Lacustrine Limnetic Unconsolidated Bottom 20,956
Total Lacustrine 20,956
Riverine Tidal Unconsolidated Bottom 17,100
Lower Perennial Unconsolidated Bottom 11,660
Upper Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
373
2,350
(2,723)
Unknown Perennial Unconsolidated Bottom 7,150
Total Riverine 38,633
TOTAL MAPPED 1,658,514
51
Wetlands of the Northeast: Results of the National Wetlands Inventory
Massachusetts
Table MA-1. Acreage of wetlands for Massachusetts based on NWI data in the national database as of September
2009. For this state, the data reflect acreage statistics for 98% of the state where NWI digital data are available (see
Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Aquatic Bed
Reef
Rocky Shore
Unconsolidated Shore
930
26
825
19,488
Total Marine 21,269
Estuarine Intertidal Aquatic Bed
Emergent
Forested
Scrub-Shrub
Reef
Rocky Shore
Unconsolidated Shore
254
44,894
2
1,009
64
130
15,501
Total Estuarine 61,854
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Cultivated Cranberry Bog
Unconsolidated Bottom
Unconsolidated Shore
684
39,682 (1,182 = tidal)
293,268 (1,808 = tidal)
84,562 (1,483 = tidal)
55
4,473
26,983 (328 = tidal)
407 (24 = tidal)
Total Palustrine 450,114 (4,825 = tidal)
Lacustrine Littoral Aquatic Bed
Emergent
Unconsolidated Bottom
Unconsolidated Shore
1,303
1,104
432
135
Total Lacustrine 2,974
52
Wetlands of the Northeast: Results of the National Wetlands Inventory
Riverine Tidal Emergent 6
Lower Perennial Rocky Shore
Unconsolidated Shore
(Subtotal)
7
65
(72)
Upper Perennial Unconsolidated Shore 21
Unknown Perennial Unconsolidated Shore 1
Intermittent Unconsolidated Shore 68
Total Riverine 168
TOTAL MAPPED 536,379
53
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table MA-2. Acreage of deepwater habitats for Massachusetts based on NWI data in the national database as of
September 2009. For this state, the data reflect acreage statistics for 98% of the state where NWI digital data are
available (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Subtidal Aquatic Bed
Unconsolidated Bottom
24,767
1,024,125
Total Marine 1,048,892
Estuarine Subtidal Aquatic Bed
Unconsolidated Bottom
7,624
89,835
Total Estuarine 97,459
Lacustrine Limnetic Aquatic Bed (AB)
Unconsolidated Bottom
Unconsolidated Bottom/AB
45
124,311
122
Total Lacustrine 124,478
Riverine Tidal Unconsolidated Bottom 951
Lower Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
7
17,244
(17,251)
Upper Perennial Unconsolidated Bottom 2,253
Unknown Perennial Unconsolidated Bottom 1,109
Total Riverine 21,564
TOTAL MAPPED 1,292,393
54
Wetlands of the Northeast: Results of the National Wetlands Inventory
New Hampshire
Table NH-1. Acreage of wetlands for New Hampshire based on NWI data in the national database as of September
2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Aquatic Bed
Rocky Shore
Unconsolidated Shore
225
161
500
Total Marine 886
Estuarine Intertidal Aquatic Bed
Emergent
Scrub-Shrub
Rocky Shore
Unconsolidated Shore
106
5,904
7
7
3,273
Total Estuarine 9,297
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Unconsolidated Bottom
Unconsolidated Shore
199
39,452 (110 = tidal)
140,451 (520 = tidal)
73,984 (164 = tidal)
1
26,101 (60 = tidal)
46
Total Palustrine 280,234 (854 = tidal)
Lacustrine Littoral Aquatic Bed
Emergent
Unconsolidated Bottom
Unconsolidated Shore
85
122
190
301
Total Lacustrine 698
Riverine Lower Perennial Unconsolidated Shore 713
Upper Perennial Rocky Shore
Unconsolidated Shore
(Subtotal)
6
701
(707)
Unknown Perennial Unconsolidated Shore 1
Intermittent Unconsolidated Shore 34
Total Riverine 1,455
TOTAL MAPPED 292,570
55
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table NH-2. Acreage of deepwater habitats for New Hampshire based on NWI data in the national database as of
September 2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Subtidal Unconsolidated Bottom 42,842
Total Marine 42,842
Estuarine Subtidal Unconsolidated Bottom (UB)
Aquatic Bed/UB
7,659
52
Total Estuarine 7,711
Lacustrine Limnetic Unconsolidated Bottom 166,859
Total Lacustrine 124,478
Riverine Tidal Unconsolidated Bottom 27
Lower Perennial Unconsolidated Bottom 17,867
Upper Perennial Unconsolidated Bottom 1,782
Unknown Perennial Unconsolidated Bottom 1
Total Riverine 19,677
TOTAL MAPPED 237,089
56
Wetlands of the Northeast: Results of the National Wetlands Inventory
New Jersey
Table NJ-1. Acreage of wetlands for New Jersey based on NWI data in the national database as of September 2009
(see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Rocky Shore
Unconsolidated Shore
12
4,212
Total Marine 4,224
Estuarine Intertidal Aquatic Bed
Emergent
Forested
Scrub-Shrub
Rocky Shore
Unconsolidated Shore
40
201,837
77
1,603
2
5,154
Total Estuarine 208,713
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Cultivated Cranberry Bog
Unconsolidated Bottom
Unconsolidated Shore
131 (17 = tidal)
67,314 (10,557 = tidal)
515,951 (18,870 = tidal)
102,610 (10,584 = tidal)
2,811
4,500
25,782 (757 = tidal)
802 (116 = tidal)
Total Palustrine 719,991 (40,901 = tidal)
Lacustrine Littoral Rock Bottom
Unconsolidated Bottom
Unconsolidated Shore
34
580
170
Total Lacustrine 784
Riverine Tidal Emergent
Unconsolidated Shore
(Subototal)
660
2,071
(2,731)
Lower Perennial Emergent
Unconsolidated Shore
(Subtotal)
57
49
(106)
Intermittent Streambed
Unconsolidated Shore
(Subtotal)
154
283
(437)
Total Riverine 3,274
TOTAL MAPPED 936,986
57
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table NJ-2. Acreage of deepwater habitats for New Jersey based on NWI data in the national database as of
September 2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Subtidal Unconsolidated Bottom 308,601
Total Marine 308,601
Estuarine Subtidal Unconsolidated Bottom 508,179
Total Estuarine 508,179
Lacustrine Limnetic Unconsolidated Bottom 50,594
Total Lacustrine 50,594
Riverine Tidal Unconsolidated Bottom 13,525
Lower Perennial Unconsolidated Bottom 12,371
Upper Perennial Rock Bottom
Unconsolidated Bottom
8
766
(774)
Total Riverine 26,670
TOTAL MAPPED 894,044
58
Wetlands of the Northeast: Results of the National Wetlands Inventory
New York
Table NY-1. Acreage of wetlands for New York based on NWI data in the national database as of September 2009. For
this state, the data reflect acreage statistics for 74% of the state where NWI digital data are available (see Figure 5 for
locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Aquatic Bed
Rocky Shore
Unconsolidated Shore
8
18
4,957
Total Marine 4,983
Estuarine Intertidal Aquatic Bed
Emergent
Forested
Scrub-Shrub
Rocky Shore
Unconsolidated Shore
249
27,684
8
1,077
69
7,074
Total Estuarine 36,161
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Unconsolidated Bottom
Unconsolidated Shore
1,208 (1 = tidal)
219,944 (1,558 = tidal)
892,019 (2,570 = tidal)
257,411 (499 = tidal)
21,731
92,773 (229 = tidal)
760
Total Palustrine 1,485,846 (4,857 = tidal)
Lacustrine Littoral Aquatic Bed
Emergent
Rocky Shore
Unconsolidated Bottom
Unconsolidated Shore
2,051
694
48
33,553
3,291
Total Lacustrine 39,637
59
Wetlands of the Northeast: Results of the National Wetlands Inventory
Riverine Tidal Aquatic Bed
Emergent
Unconsolidated Shore
(Subototal)
4
9
427
(440)
Lower Perennial Aquatic Bed
Emergent
Rocky Shore
Unconsolidated Shore
(Subtotal)
1,151
164
15
1,593
(2,923)
Upper Perennial Unconsolidated Shore 1,658
Unknown Perennial Emergent
Rocky Shore
Unconsolidated Shore
(Subtotal)
71
11
72
(154)
Intermittent Streambed
Unconsolidated Shore
(Subtotal)
38
913
(951)
Total Riverine 6,126
TOTAL MAPPED 1,572,753
60
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table NY-2. Acreage of deepwater habitats for New York based on NWI data in the national database as of September
2009. For this state, the data reflect acreage statistics for 74% of the state where NWI digital data are available (see
Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Subtidal Aquatic Bed
Unconsolidated Bottom
1,501
784,398
Total Marine 785,899
Estuarine Subtidal Aquatic Bed
Unconsolidated Bottom
28,374
818,864
Total Estuarine 847,238
Lacustrine Limnetic Aquatic Bed
Unconsolidated Bottom
152
1,174,429
Total Lacustrine 1,174,581
Riverine Tidal Unconsolidated Bottom 25,425
Lower Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
3
105,090
(105,093)
Upper Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
441
12,203
(13,644)
Unknown Perennial Unconsolidted Bottom 1,065
Total Riverine 145,227
TOTAL MAPPED 2,952,945
61
Wetlands of the Northeast: Results of the National Wetlands Inventory
Pennsylvania
Table PA-1. Acreage of wetlands for Pennsylvania based on NWI data in the national database as of September 2009
(see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Estuarine Intertidal Unconsolidated Shore 55
Total Estuarine 55
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Rock Bottom
Unconsolidated Bottom
Unconsolidated Shore
1,314
59,023 (200 = tidal)
219,101 (220 = tidal)
79,589 (13 = tidal)
2
92
60,452 (5 =tidal)
545 (41 = tidal)
Total Palustrine 420,118 (479 = tidal)
Lacustrine Littoral Aquatic Bed
Emergent
Rock Bottom
Rocky Shore
Unconsolidated Bottom
Unconsolidated Shore
892
266
95
120
6,215
1,221
Total Lacustrine 8,809
Riverine Tidal Emergent
Unconsolidated Shore
(Subtotal)
157
760
(917)
Lower Perennial Emergent
Rocky Shore
Unconsolidated Shore
(Subtotal)
517
31
1,088
(1,636)
Upper Perennial Rocky Shore
Unconsolidated Shore
(Subtotal)
67
434
(501)
Unknown Perennial Emergent
Unconsolidated Shore
(Subtotal)
88
248
(336)
Intermittent Unconsolidated Shore 275
Total Riverine 3,665
TOTAL WETLANDS 432,647
62
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table PA-2. Acreage of deepwater habitats for Pennsylvania based on NWI data in the national database as of
September 2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Estuarine Subtidal Unconsolidated Bottom (UB) 647
Total Estuarine 647
Lacustrine Limnetic Aquatic Bed (UB)
Unconsolidated Bottom (UB)
69
312,140
Total Lacustrine 312,209
Riverine Tidal Unconsolidated Bottom 9,478
Lower Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
92
139,232
(139,324)
Upper Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
46
13,462
(13,508)
Unknown Perennial Unconsolidated Bottom 8,421
Total Riverine 170,731
TOTAL MAPPED 483,587
63
Wetlands of the Northeast: Results of the National Wetlands Inventory
Rhode Island
Table RI-1. Acreage of wetlands for Rhode Island based on NWI data in the national database as of September 2009
(see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Aquatic Bed
Rocky Shore
Unconsolidated Shore
1
215
714
Total Marine 930
Estuarine Intertidal Aquatic Bed
Emergent
Forested
Scrub-Shrub
Rocky Shore
Streambed
Unconsolidated Shore
42
3,678
80
3
62
4
3,419
Total Estuarine 7,288
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Cultivated Cranberry Bog
Unconsolidated Bottom
Unconsolidated Shore
37
3,051 (34 = tidal)
48,665 (94 = tidal)
5,887 (16 = tidal)
107
4,680 (25 = tidal)
27 ( 8 = tidal)
Total Palustrine 62,454 (177 = tidal)
Lacustrine Littoral Emergent
Unconsolidated Shore
4
2
Total Lacustrine 6
TOTAL WETLANDS 70,678
64
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table RI-2. Acreage of deepwater habitats for Rhode Island based on NWI data in the national database as of
September 2009 (see Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Subtidal Aquatic Bed
Unconsolidated Bottom
1,175
171,455
Total Marine 172,630
Estuarine Subtidal Aquatic Bed
Unconsolidated Bottom
357
88,033
Total Estuarine 88,390
Lacustrine Limnetic Unconsolidated Bottom 19,484
Total Lacustrine 19,484
Riverine Tidal Unconsolidated Bottom 20
Lower Perennial Unconsolidated Bottom 1,059
Total Riverine 1,079
TOTAL MAPPED 281,583
65
Wetlands of the Northeast: Results of the National Wetlands Inventory
Vermont
Table VT-1. Acreage of wetlands for Vermont based on NWI data in the national database as of September 2009. For
this state, the data reflect acreage statistics for 99% of the state where NWI digital data are available (see Figure 5 for
locations and effective date of data based on imagery).
System Subsystem Class Acreage
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Unconsolidated Bottom
Unconsolidated Shore
583
47,222
117,801
59,947
1,114
13,717
80
Total Palustrine 240,464
Lacustrine Littoral Aquatic Bed
Emergent
Unconsolidated Bottom
Unconsolidated Shore
1,188
28
21,129
92
Total Lacustrine 22,437
Riverine Lower Perennial Unconsolidated Shore 242
Upper Perennial Rocky Shore
Unconsolidated Shore
(Subtotal)
2
193
(195)
Intermittent Unconsolidated Shore 45
Total Riverine 482
TOTAL MAPPED 263,383
66
Wetlands of the Northeast: Results of the National Wetlands Inventory
Table VT-2. Acreage of deepwater habitats for Vermont based on NWI data in the national database as of September
2009. For this state, the data reflect acreage statistics for 99% of the state where NWI digital data are available (see
Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Lacustrine Limnetic Aquatic Bed (AB)
AB/Unconsolidated Bottom
Unconsolidated Bottom (UB)
UB/Aquatic Bed
19
2,516
196,871
20
Total Lacustrine 199,426
Riverine Lower Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
6
10,698
(10,704)
Upper Perennial Rock Bottom
Unconsolidated Bottom
(Subtotal)
171
2,466
(2,637)
Total Riverine 13,341
TOTAL MAPPED 212,767
67
Wetlands of the Northeast: Results of the National Wetlands Inventory
Virginia
Table VA-1. Acreage of wetlands for Virginia based on NWI data in the national database as of September 2009 (see
Figure 5 for locations and effective date of data based on imagery).
System Subsystem Class Acreage
Marine Interidal Aquatic Bed
Reef
Unconsolidated Shore
37
55
4,285
Total Marine 4,377
Estuarine Intertidal Aquatic Bed
Emergent
Forested
Scrub-Shrub
Reef
Rocky Shore
Unconsolidated Shore
724
197,335
3,670
3,961
705
5
143,789
Total Estuarine 350,189
Palustrine -- Aquatic Bed
Emergent
Forested
Scrub-Shrub
Farmed
Unconsolidated Bottom
Unconsolidated Shore
644 (23 = tidal)
107,743 (21,839 = tidal)
811,100 (56,238 = tidal)
103,902 (8,123 = tidal)
1,171
82,291 (738 = tidal)
1,164 (10 = tidal)
Total Palustrine 1,108,015 (86,971 = tidal)
Lacustrine Littoral Aquatic Bed
Emergent
Unconsolidated Bottom
Unconsolidated Shore
118
198
3
1,462
2,612
Total Lacustrine 4,393
68
Wetlands of the Northeast: Results of the National Wetlands Inventory
Riverine Tidal Emergent
Unconsolidated Shore
(Subtotal)
500
2,047
(2,547)
Lower Perennial Aquatic Bed
Rocky Sho